bluuebunny/crossref_metadata_2025 huggingface dataset:
Carbon‐13 nuclear magnetic resonance of some acetylenic compounds
Authors: Rosenberg D. , Drenth W. , de Haan J. W.
Published: September 2010

13C nuclear magnetic resonances were measured for heterosubstituted acetylenes. The chemical shifts of the acetylenic carbon atoms are influenced in two ways:

by charge transfer to the triple bond as in C CO, or from the triple bond as in magnified image

by polarisation of the charge in the triple bond in the above‐mentioned systems and in C  CS.
Conformation of open‐chain compounds. Part 3. Carbon‐halogen stretching frequencies and conformation of some vicinal dihalides
Authors: Altona C. , Hageman H.J.
Published: September 2010

A study of the infrared and Raman spectra of some vicinal dihalogeno‐ethanes, ‐propanes and ‐butanes with predominant antiperiplanar orientation in the straight chain and branched series, reveals that the two C‐Hal stretching frequencies occur characteristically as a more or less strongly coupled pair: an intense Raman band (νs) and a strong infrared active mode of vibration (νas) at lower frequencey.

The C‐Hal frequencies of the gauche conformations are weakly coupled.

The position of the bands and the difference Δν = νs − νas are functions of the chemical/geometrical structure in the vicinity of the C‐Hal bonds. Empirical rules are presented by which the C‐Hal frequencies or, in strongly coupled systems, the average frequency of anti as well as of gauche forms can be predicted with fair accuracy.
The conformation of non‐aromatic ring compounds. Part 39. Dipole Moments and Conformational Properties of some trans‐1, 2‐Dihalogenocyclohexanes and their alkyl derivatives
Authors: Hageman H.J. , Havinga E.
Published: September 2010

A number of trans‐1,2‐dihalogenocyclohexanes and their alkyl homologues have been synthesized and their dipole moments determined in carbon tetrachloride and in benzene. The diaxial conformation is found to be favoured except in cases of considerable syn‐diaxial crowding. From the dipole data of some 4‐methyl derivatives a “ΔG°e‐a” of 1.8 kcal/mole for the methylgroup has been calculated. Similar calulations have led to much lower ΔG°e‐a values in the case of 1‐alkyl derivatives: 0.6 kcal/mole for the methyl group and 1.1 kcal/mole for the ethyl group. Values of ∼ 3.5 kcal/mole have been calculated for the syn‐diaxial methyl ‐ bromine interaction in some 4,4‐dimethyl derivatives. Values of 2‐3 kcal/mole have been obtained for the corresponding methyl ‐ chlorine interaction.

The magnitude of the aa ± ee equilibrium shift towards the ee form going from carbon tetrachloride to benzene as a solvent, seems to be characteristically constant (0.5 kcal/mole) in the case of the trans‐1,2‐dibromo(chloro)‐ cyclohexanes and ‐alkylcyclohexanes.
The heat of combustion of benzoic acid NBS standard sample 39i
Authors: Mosselman C. , Dekker H.
Published: September 2010

The heat of combustion of benzoic acid NBS standard sample 39i supplied by the National Bureau of Standards (Washington) was measured. The mean value under standard bomb conditions was found to be:

26431.9 ± 1.6 J per gram.

Measures leading to a high precision are given. Systematic errors were studied.
Ester hydrolysis in concentrated sulfuric acid
Authors: van Bekkum H. , Buurmans H. M. A. , Wepster B. M. , van Wijk A. M.
Published: September 2010

Aliphatic and alicyclic esters are found to be hydrolyzed conveniently and without epimerization in concentrated sulfuric acid at room temperature. First‐order kinetics are observed. A Hammett rho value of ‐3.6 applies for the hydrolysis of methyl benzoates. Sterically hindered esters show increased rates of hydrolysis. These findings are in accordance with the AAc 1 mechanism.
New musk odorants VI. The formation of 1,1‐dimethyl‐7‐isopropyltetralinviaa novel rearrangement‐dehydrogenation of longifolene
Authors: Kettenes D. K. , van Lierop J. B. H. , van der Wal B. , Sipma G.
Published: September 2010

1,1‐Dimethyl‐7‐isopropyltetralin (II) is formed in up to 40% yield by a ZnCl2‐catalyzed rearrangement‐dehydrogenation of longifolene (I), or isolongifolene (III). The structural proof of II is based on spectroscopic and chemical evidence. Acetylation and formylation of II yielded products with a weak musk odour.
The synthesis of some bicycloheterenes
Authors: Wynberg Hans , Klunder A. J. H.
Published: September 2010

This paper deals with the synthesis of some bicycloheterenes. 4,5,6,7‐Tetrahydro‐1,3‐dimethyl‐4,7‐methanobenzo[c]thiophene (I), 4,5,6,7‐tetrahydro‐1, 3‐dimethyl‐4,7‐ethanobenzo[c]thiophene (II), 4,7‐dihydro‐1, 3‐dimethyl‐4,7‐ethanobenzo[c]thiophene (III) and 4,5,6,7‐tetrahydro‐1,3‐dimethyl‐2‐phenyl‐4,7‐ethanobenzo[c]pyrrole (IV) were obtained by ring‐closure of the corresponding bicyclic 1,2‐diacetyl compounds.
Poisoning effects of hydrogen sulfide on noble metal electrodes Part II. Effect of H2S on periodic current vs. potential curves of Pt and Au electrodes in 0.5 M H2SO4
Authors: Ijzermans A. B.
Published: September 2010

Periodic current vs. potential curves have been measured on Pt, platinized Pt, Au and Au/Pt electrodes in 0.5 M H2SO4 saturated with H2S, and a comparison has been made with curves obtained in H2S‐free solutions. It may be seen that the current peaks characteristic of the reactions of chemisorbed oxygen and hydrogen are suppressed for the greater part under the influence of H2S.
The ligand properties of pyridine‐N‐oxide. Extension and discussion
Authors: Reedijk J.
Published: September 2010

A number of 15 new solvates containing pyridine‐N‐oxide of the general formula M(C5H5NO)mn+ (anion)n− is reported. In these compounds M = Li, Na, Mg, Ca, Sr, Ba, Mn, Fe, Co, Cu, Zn, Cd, Pb, and Tl, n = 1‐3, m = 3‐8, and the anions are ClO4− and BF4−.

The compounds are identified by chemical analysis and by means of physical measurements.

The shift towards lower wave numbers in the N‐O stretching frequency of the complexes is discussed. Far‐infrared spectra in the region 700‐200 cm−1 have also been investigated. A correlation between νNO and νMO is reported.

Ligand‐field spectra for the transition‐metal solvates of Co(II) and Ni(II) have been re‐investigated. New values for Dq and B are reported, and the ligand is placed in the spectrochemical and nephelauxetic series.

The Mössbauer spectrum of Fe(C5H5NO)6(ClO4)2 is discussed. Electron paramagnetic resonance spectra of the solvates of Mn(II), Ni(II), and Cu(II) have been investigated. No static Jahn‐Teller distortion of the species Cu(C5H5NO)62+ is observed at room temperature.

Pyridine‐N‐oxide is concluded to be a rather strong ligand, as reflected by the facts that preparation of metal solvates is often possible from the hydrated metal salts without dehydration, and the rather high values of Dq/B calculated from the spectra of the cobalt(II) and nickel(II) solvates.
Reaction of α,β‐unsaturated ethers, amines, thioethers and selenoethers with lithium in liquid
Authors: Brandsma L. , Schuijl P. J. W.
Published: September 2010

α,β‐Unsaturated thioethers RCH=CHSR′ (R=H, alkyl; R′ = alkyl, ‐CH=CHR, ‐C≡CR) and RC≡CSR′(R =alkyl;R′ = alkyl, ‐C≡CR) are cleaved by lithium in liquid ammonia to afford alkenethiolates RCH=CHSLi and alkynethiolates RC≡CSLi, respectively. Subsequent alkylation with R″Br gives the analogous α,β‐unsaturated thioethers RCH=CHSR″ and RC≡CSR″ in good to excellent yields. A similar result is obtained with the selenoether (CH3CH=CH)2Se.

1‐Ethoxy‐1‐pentyne C3H7C≡COC2H5 and 1‐(N,N‐diethylamino)‐1‐hexyne C4H9C≡CN(C2H5)2 are reduced to trans‐C3H7CH=CHOC2H5 and trans‐C4H9CH=CHN(C2H5)2 with good yields. Treatment of ketene dithioacetals RCH=C(SR′)2 (R = H or alkyl, R′ = alkyl) with two equivalents of lithium and subsequent addition of ammonium chloride or water affords dithioesters magnified image.
The crystal structure of “anhydrous manganic acetate”
Authors: Hessel L. W. , Romers C.
Published: September 2010

“Anhydrous manganic acetic” is a linear polymer with the empirical formula [Mn3O(OAc)6 · AcOH · OAc]n. The three manganese atoms in the monomeric unit are mutually connected by three pairs of acetate bridges and form an equilateral triangle with an oxygen atom in its centre. Acetic acid molecules and acetate bridges between the monomeric units complete the distorted octahedral coordination about the manganese atoms.
Base induced reactions of 1‐alkoxy‐ or l‐methylthio‐l‐(α‐ or β‐hydroxyalkyl)allenes. Formation of 3‐alkoxy‐ and 3‐methylthiodihydrofurans
Authors: Hoff S. , Brandsma L. , Arens J. F.
Published: September 2010

l‐Alkoxy‐l‐(α‐hydroxyalkyl)allenes R1CH=C=C(OR2)C(OH)R3R4 (Ia) have been converted with high yields into 3‐alkoxy‐2,5‐dihydrofurans (II) using potassium tert‐butoxide in dimethyl sulfoxide. Hydrolysis of II with dilute sulfuric acid afforded 3‐oxotetrahydrofuran derivatives III. l‐(β‐Hydroxyalkyl)‐l‐methylthioallenes R1CH=C=C(SCH3)CH2CH2OH (IVb) and the analogous oxygen compounds IVa yielded 2‐alkyl‐3‐methylthio‐4,5‐dihydrofurans (Vb) and a mixture of 3‐methoxy‐2‐methyl‐4,5‐dihydrofurans (Va) and 3‐methoxy‐2‐methylenetetrahydrofuran VI, respectively. The preparation of the hydroxyallenes is described.
Potassium tert‐butoxide‐catalyzed isomerization of methyl linoleate in tert‐butanol and mixtures of tert‐butanol and ethylene glycol dimethyl ether: A kinetic investigation
Authors: Korver O. , Boelhouwer C.
Published: September 2010

A kinetic investigation is reported of the potassium tert‐butoxide catalyzed isomerization of methyl linoleate in tert‐butanol and mixtures of tert‐butanol and ethylene glycol dimethyl ethers.

The product is a mixture of 9cis, 11 trans and 10trans, 12cis methyl octadienoates.

The reaction is first order in olefin and 1.5 order in base over the entire range of base concentrations (0.05 to 1 M).

The order in base and the acceleration of the reaction by addition of ethylene glycol dimethyl ethers are discussed.
Investigations on sterols XXXIII: Synthesis of 18‐alkyl‐9β,10α‐pregnane derivatives
Authors: van Moorselaar R. , Halkes S.J.
Published: September 2010

The 20‐cyanohydrin of 9β,10α‐progesterone was converted into 18‐cyano‐9β,10α‐progesterone by the so‐called hypoiodite reaction. The latter compound was used as a starting material for the synthesis of several 18‐alkyl‐9β,10α‐pregnanes. Interesting biological activities were found in the 18‐methyl‐9β,10α‐pregnane series.
Investigations on sterols XXXIV: Synthesis of 18‐methyl‐9β,10α‐androstanes
Authors: Halkes S.J. , van Moorselaar R.
Published: September 2010

Chemical degradation of the side chain of 18‐methyl‐9β, 10α‐progesterone gave 18‐methyl‐9β,10α‐androst‐4‐ene‐3,17‐dione in an overall yield of 45‐50%. Starting from this compound several substituted 18‐methyl‐9β,10α‐androstanes were synthesized, for which interesting biological activities were found.
Hydrogenation of 1,3,5‐tri‐t‐butylbenzene over platinum and palladium: Synthesis of cis,cis‐ and cis,trans‐1,3,5‐tri‐t‐butylcyclohexane
Authors: van Bekkum H. , Buurmans H. M. A. , van Minnen‐Pathuis G. , Wepster B. M.
Published: September 2010

The liquid phase hydrogenation of 1,3,5‐tri‐t‐butylbenzene (I) over palladium, platinum and rhodium has been studied. Cis‐1,3,5‐tri‐t‐butylcyclohexene (II) is shown to be an important intermediate in the hydrogenation of I. The rates of hydrogenation of I, II, and some other alkylsubstituted benzenes and cyclohexenes over palladium and platinum have been compared.

The isomeric 1,3,5‐tri‐t‐butylcyclohexanes and 1,3,5‐tri‐t‐butylcyclohexenes have been prepared. The conformation of cis, trans‐1,3,5‐tri‐t‐butylcyclohexane
C‐nitroso compounds. Part X: C‐nitroso compounds as hydrogen bond acceptors
Authors: Engberts J. B. F. N. , Wajer Th. A. J. W. , Kruk C. , de Boer Th. J.
Published: September 2010

Intermolecular hydrogen bonding between phenol and a series of monomeric and trans‐dimeric C‐nitroso compounds has been studied by IR and PMR spectroscopy.

The rather small OH stretching frequency shifts Δv for monomeric C‐nitroso compounds indicate a weak “ground state” basicity for the NO group. For five p‐substituted nitrosobenzenes Δv values are correlated by σ+ substituent constants. Trans‐dimeric C‐nitroso compounds form stronger hydrogen bonds than the corresponding monomers, resulting in a shift of the monomer‐trans‐‐dimer equilibrium upon addition of a proton donor like phenol.
Aromatic sulfonation. Part 24: Kinetics and mechanism of the sulfonation of o‐ and m‐xylene in aqueous sulfuric acid
Authors: Prinsen A. J. , Cerfontain H.
Published: September 2010

The sulfonation of o‐ and m‐xylene in concentrated aqueous sulfuric acid has been investigated. Rates and isomer distributions have been measured. The results are discussed in terms of two sulfonating mechanisms. The isomer distributions at 25.0° for the mechanism with H2S2O7 as sulfonating entity are 45.1 ± 0.4% 3‐ and 54.9 ± 0.4% 4‐substitution for o‐xylene, and 14.5 ± 0.6% 2‐, 84.3 ± 0.6% 4‐ and 1.2 ± 0.2% 5‐substitution for m‐xylene. For the mechanism with H3SO4+ as sulfonating entity these data are 6.5 ± 0.9%, 3‐ and 93.5 ± 0.9% 4‐substitution with o‐xylene, and 0.5 ± 0.2% 2‐, 98.9 ± 0.4% 4‐ and 0.6 ± 0.2% 5‐substitution with m‐xylene. The smaller degree of 3‐substitution with o‐xylene for the H2S2O7 ‐ as compared with the H3SO4+ ‐ mechanism is mainly due to a difference in entropy of activation. The former mechanism encounters more steric hindrance than the latter on substitution ortho to a methyl group. The experimental partial rate factors for the three isomeric xylenes for the two sulfonation mechanisms differ by less than a factor of 4 from those calculated on the basis of additivity of substituent effects with the exception of the 2‐position of m‐xylene, for sulfonation by the entity H3SO4+, and of the 2‐ and 4‐positions of m‐xylene for sulfonation by the entity H2S2O7.
Oxidative coupling of alkyl‐substituted catechols with phloroacylophenones
Authors: Overeem J. C.
Published: September 2010

Oxidative coupling of 4‐methylcatechol with phloroacetophenone and methylphloroacetophenone leads to 6‐acetyl‐4,4a‐dihydro‐7,9‐dihydroxy‐4a‐methyl‐2,3‐dibenzofurandione (Ie) and 6‐acetyl‐4,4a‐dihydro‐7,9‐dihydroxy‐4a,8‐dimethyl‐2,3‐dibenzofurandione (IIe), respectively.

The same type of compound is formed when using 3,5‐dimethyl, 3,4‐di‐methyl‐ or 3,4,6‐trimethyl‐catechols instead of 4‐methylcatechol. However, 3,4‐dimethyl‐ and 3,4,6‐trimethyl‐catechols give mainly compounds which are derivatives of 2(4aH)‐dibenzofuranone.
Aromatic sulfonation 25: Kinetics and mechanism of the sulfonation of fluoro‐, bromo‐ and iodo‐benzene in aqueous sulfuric acid
Authors: Kort C. W. F. , Cerfontain H.
Published: September 2010

Rates and isomer distributions have been determined for the sulfonation of fluoro‐, bromo‐ and iodo‐benzene in 83‐98% sulfuric acid at 25°. The results are analogous to those for chlorobenzene 1. It is shown that the mechanism proposed previously1 is incorrect The σ‐complex formed in the rate‐limiting reaction of ArH with H2S2O7 is not magnified image
The conformation of non‐aromatic ring compounds 53: The crystal structure of 22,23‐dibromo‐9β‐ergost‐4‐en‐3‐one (Determined at ‐180°C and at 20°C)
Authors: Hesper B. , Geise H. J. , Romers C.
Published: September 2010

The compound 22,23‐dibromo‐9β‐ergost‐4‐en‐3‐one crystallizes in the orthorhombic space group P212121 with four molecules per unit cell. Lattice constants measured at ‐ 180° are a = 34.19, b = 12.44 and c = 6.09 Å. The structure was solved by the heavy‐atom technique refined by the method of least squares, the final R value being 9.6%.

This steroid molecule belonging to the 8β, 9β,10β‐series has a cis‐B/C junction which gives rise to unusual twist‐boat conformations for rings B and C. An explanation is given in terms of torsional angles. The conformation of ring D is nearly a C13 envelope.
Preparation, properties and absolute configuration of (‐)‐allantoin
Authors: 's‐Gravenmade E. J. , Vogels G. D. , van Pelt Corry
Published: September 2010

A procedure is given for the preparation and isolation of (‐)‐allantoin (5‐ureidohydantoin). A grown culture of Pseudomonas aeruginosa was incubated with (±)‐allantoin at pH 6. (+)‐Allantoin was degraded by the bacteria and (‐)‐allantoin was removed from the medium with the aid of activated carbon.

Several properties of (‐)‐allantoin were determined: solubility and molar rotation in various solvents, infrared spectrum, decomposition point and dependence of the molar rotation on pH. The properties were compared with those of (±)‐allantoin, R‐ and S‐hydantoin‐5‐acetic acid.

From circular dichroism measurements of (‐)‐allantoin, S‐hydantoin‐5‐acetic acid and R‐carbamoylalanine it was concluded that (‐)‐allantoin is R‐allantoin.
Hydrolysis and racemization of allantoin
Authors: Vogels G. D. , de Windt F. E. , Bassie W.
Published: September 2010

The rates of hydrolysis and racemization of allantoin (5‐ureidohydantoin) were measured as a function of pH and temperature. Both reactions are susceptible to acid and base catalysis. Spontaneous hydrolysis of the neutral and anionic forms of allantoin determines the rate‐pH profile at pH values from 2 to 13.

Allantoin is converted to allantoate (diureidoacetate) which is transformed to glyoxylate and urea in acid media. At pH values ∼ 3 ammonia is formed directly from the ureido grouping of allantoin.

The rates of racemization of (‐)‐allantoin and of L(‐)‐ and D(+)‐hydantoin‐5‐acetic acid were compared. Both reactions involved most probably enolization of the moiety of the hydantoin rings.
Hydrolysis of allantoate
Authors: Vogels G. D. , van Der Drift C.
Published: September 2010

The rate of hydrolysis of allantoate (diureidoacetate) was measured as a function of temperature and pH. Similar experiments were performed with urea and N‐carbamoylglycine (hydantoate) and the results were compared. At pH values below 7 allantoate was converted to ureidoglycolate and urea. The equilibrium position of this conversion was determined as a function of temperature. In alkaline media isocyanate, ammonia, glyoxylate and urea were formed from allantoate. The reaction rate of this conversion was similar to those measured in urea and N‐carbamoylglycine hydrolyses.
A gas‐chromatographic investigation of the thermodynamics of solutions of monosubstituted hexane, cyclohexane, benzene and pyridine derivatives and of some tetra‐alkyl compounds in apiezon M
Authors: Hammers W. E. , de Ligny C. L.
Published: September 2010

From retention volumes, determined over a range of temperatures, standard partial molar free enthalpies, enthalpies and entropies of vaporization from infinitely dilute solution in apiezon M are calculated and discussed. Particular attention is paid to the possibility of restricted molecular rotation of the solute molecules, the validity of Butler's additivity rule for the free enthalpy of vaporization and the applicability of the regular solution theory to the enthalpy of mixing of the liquid solutes with apiezon.
Complexes with ligands containing the carbonyl group. Part I: Complexes with acetone of some divalent metals containing tetrachloro‐ferrate(III) and ‐indate(III) anions
Authors: Driessen W. L. , Groeneveld W. L.
Published: September 2010

A series of new complexes is reported with acetone as the ligand: viz. [M(CH3COCH3)62+][A−]2 where M is Mg(II), Ca(II), Sr(II), Mn(II), Fe(II), Co(II), Ni(II), and Zn(II); and A− is FeCl−4 and InCl−4.

In the complexes, the carbonyl vibration is shifted to lower frequencies and the CO bending, the CO deformation, and the CCC deformation vibrations are shifted to higher frequencies with regard to the vibrations in the free ligand. The magnitudes of the shifts are dependent on the metal ions. In the far infrared a metal‐dependent absorption band appears, which is attributed to the metal‐ligand stretching vibration.

Investigation of ligand field spectra indicates the presence of octahedral species M(acetone)62+ in the solid compounds. Values for Dq and B′ are reported and the ligand is placed in the spectrochemical and nephelauxetic series.
Synthesis of the sequence of oxytocin on a hydroxymethylstyrene‐divinylbenzene polymer
Authors: Beyerman H. C. , in 'T Veld R. A.
Published: September 2010

The preparation of a hydroxymethylstyrene‐2%‐divinylbenzene polymer is described.

The optimal method for the esterification of this polymer with N‐t‐butoxy‐carbonyl amino acids was found by using N,N′‐carbonyldiimidazole, the remaining hydroxyl groups being protected by formation of their acetates.

On this polymer the nonapeptide sequence of the hormone oxytocin was synthesized and then split off in two ways. Tertiary base‐catalysed methanolysis (found in this Laboratory) gave the nonapeptide methyl ester: Z‐Cys(BZL)‐Tyr‐Ile‐Gln‐Asn‐Cys(BZL)‐Pro‐Leu‐Gly‐OMe

a. L‐Amino acids are meant. b. Abbreviations used here and later: IUPAC, Information Bulletin 25, February 1966, 32‐40; 26, August 1966, 11‐19; 27, December 1966, 16‐18; 30, October 1967, 27‐32.

, and ammoniacal methanol gave the carboxy‐terminal amide: Cys(BZL)‐Tyr‐Ile‐Gln‐Asn‐Cys(BZL)‐Pro‐Leu‐Gly‐NH2(H2O · HBr).

The usual debenzylation and cyclization of the amide gave biologically active material.
A chelate of ZnCl2 with ethylenediiminobisacetylacetone
Authors: Bellaart A. C. , van den Dungen G. J. , Kuijer M. , Verbeek J. L.
Published: September 2010

Unsuccessful attempts to prepare ethylenediiminobisacetylacetonezinc led to the isolation of a novel compound ethylenediiminobisacetylacetonezinc dichloride following a procedure similar to that introduced by Ramaiah and Martin

K. Ramaiah and D. F. Martin, J. Inorg. Nucl. Chem. 27, 1663 (1965).

. A tentative structure of ethylenediiminobisacetylacetonezinc dichloride is proposed from UV, IR, NMR, and conductance data.
Ring transformations in reactions of heterocyclic halogeno compounds with nucleophiles (XVIII): Pyrimidines (XVIII). D/H exchange studies during the conversion of 2‐substituted 4‐chloropyrimidines into 2‐substituted 4‐methyl‐s‐triazines by treatment with potassium amide in liquid ammonia
Authors: van der Plas H. C. , Zuurdeeg B. , van Meeteren H. W.
Published: September 2010

4‐Chloro derivatives of 2‐piperidino‐ and 2‐morpholinopyrimidine are converted by potassium amide in liquid ammonia into 2‐piperidino‐ and 2‐morpholino‐4‐methyl‐s‐triazine, respectively, in about 80‐85% yield. From the results of the reactions of the 6‐monodeuterio and the 5,6‐dideuterio derivatives of 4‐chloro‐2‐morpholinopyrimidine with the same reagent it has been concluded that during the reaction course an intermediate must be present which contains an acidic hydrogen. An acetylenic intermediate is proposed.
Formation of acetylenic dithioesters from substituted allenyl vinyl sulfides: A new type of thio‐claisen rearrangement
Authors: Schuijl P. J. W. , Brandsma L.
Published: September 2010

The ketene dithioacetals CH2C(SC2H5)SC(R)CCH2 (with R  H or C2H5) are converted into acetylenic dithioesters RC ≡ CCH2CH2C(S)SC2H5 upon heating at 80–110°. The starting compounds are prepared by treating the ketene dithioacetals H2CC(SC2H5)SC≡CCH3 with lithium amide in liquid ammonia and subsequently hydrolysing with water or alkylating with ethyl bromide.
A voltammetric study of the diffusion of ferrocyanide ion in aqueous solution
Authors: Powell F. E.
Published: September 2010

In a voltammetric study of the diffusion of ferrocyanide ion to a platinum microelectrode at 25°C the diffusion area is calculated from the Cottrell equation in the case of chronoamperometry, and from the Sand equation, in the case of chronopotentiometry. The values obtained are used to calculate the relative diffusion coefficients of the ion at other temperatures.
Deazapurine derivatives. V: A new synthesis of 1‐ and 3‐deaza‐adenine and related compounds
Authors: de Roos K. B. , Salemink C. A.
Published: September 2010

Reinvestigation of the cyclization of 2,3,4‐triaminopyridine (1) by several procedures showed that both 7‐aminoimidazo[4,5‐b]pyridine (1‐deaza‐adenine, II) and 4‐aminoimidazo[4,5‐c]pyridine (3‐deaza‐adenine, III) were always obtained. A new and convenient route to the synthesis of II has been devised. Also an unambiguous synthesis of III is given. Ring closure of 2,4,5‐triamino‐pyridine (XIX) afforded 6‐aminoimidazo[4,5‐c]pyridine (3‐deazaisoadenine, XX).
Electrochemical reduction of AZA aromatics: Part II. Protonation products of di‐aza aromatics
Authors: van Der Meer D.
Published: September 2010

The formation of proton products plays an essential part in the explanation of the reduction mechanism of the di‐aza aromatics in dimethylformamide (DMF). By recording cyclic polarograms of the di‐aza aromatics and comparing them with those obtained from the protonated products of the di‐aza aromatics it is sometimes possible to identify the proton products which are formed in the reduction process. From the experimental evidence and from calculations by means of the HMO method it can be shown that protonation of the mononegative ions is the first step in the dimerization of quinazoline, phthalazine and pyrimidine.
Derivatives of furan and 2,5‐dihydrofuran from cumulenic carbinol ethers
Authors: Rompes J. A. , Hoff S. , Montijn P. P. , Brandsma L. , Arens J. F.
Published: September 2010

Treatment of the carbinols (CH3)2C=C=C=C(OCH3)CR1R2(OH) (I) with potassium tert‐butoxide in dimethyl sulfoxide gives derivatives of furan (III) if R2 = H and derivatives of 2,5‐dihydrofuran (II) if R1 and R2 are both alkyl or if R1R2C = cyclohexyl. Acid‐catalysed hydrolysis of II and III affords derivatives of 3‐oxo‐2,3‐dihydrofuran (IV).

Potassium amide in liquid ammonia, when used in excess, causes isomerisation of I into CH2=C(CH3)CH=C=C(OCH3)CR1R2(OH) (Ia).
Deazapurine derivatives. VI: Synthesis of 1,2,5‐thia‐ and 1,2,5‐selena‐diazolopyridines
Authors: Harts G. H. , de Roos K. B. , Salemink C. A.
Published: September 2010

1,2,5‐Thiadiazolo[3,4‐b]‐ and 1,2,5‐thiadiazolo[3,4‐c]‐pyridines have been synthesized from the appropriate diaminopyridines and thionyl chloride. Ring closure of the diamines with selenious acid gave the corresponding selenadiazolopyridines.
Ketenes with the adamantane skeleton
Authors: Strating J. , Scharp J. , Wynberg Hans
Published: September 2010

The preparation of solutions of the three simplest ketenes containing the adamantane moiety is described. Initial studies show significant differences in their chemical behaviour, especially with respect to their tendency to polymerize.
Stereochemistry of base‐catalysed double‐bond migration in allyl ethers
Authors: Kloosterziel H. , van Drunen J. A. A.
Published: September 2010

Base‐catalysed isomerization of trans‐3‐methoxy‐1‐phenylpropene (A) yields stereospecifically as the initial product cis‐1‐methoxy‐3‐phenylpropene (B). This is caused by the (intermediate) formation of the cis‐1‐methoxy‐trans‐3‐phenylallyl anion (II‐1), which is energetically favoured over the trans‐isomeric anion (I). The NMR spectra of I and II‐1 are described.
Stereochemistry of base‐catalysed double‐bond migration in inner olefins
Authors: Kloosterziel H. , van Drunen J. A. A.
Published: September 2010

The mechanism of the title reaction is discussed. The NMR spectra of the 1‐methyl‐ and 1,3‐dimethyl‐1‐phenylallyl and of the 3‐methyl‐ and 1,3‐dimethyl‐oxapentadienyl anions are given.
Protonation of 9‐ethyl‐10‐methylanthracene: Absence of a large Baker‐Nathan effect in alkylarenium‐ion formation
Authors: Brouwer D. M. , van Doorn J. A.
Published: September 2010

Protonation of 9‐ethyl‐10‐methylanthracene in HF or CF3COOH/H2O · BF3 affords a mixture of the 9H+‐ and 10H+‐9‐ethyl‐10‐methylanthracenium ions. These ions differ in free energy by only 0.9‐1.0 kcal · mole−1. This small difference in stability, which is probably due to steric rather than electronic effects, shows that methyl and ethyl groups are approximately equally effective in stabilizing arenium ions. This result demonstrates, contrary to what was recently concluded1 on the basis of calorimetric measurements of the heats of protonation of alkylbenzenes in FSO3HSbF5, that there is no large Baker‐Nathan effect in alkylarenium‐ion formation.

The PMR‐spectrum of the 9H+‐9‐ethyl‐10‐methylanthracenium ion exhibits some remarkable features ‐ notably an unusually strong shielding of the ethyl‐CH3 protons · that are associated with the particular conformation of the (>CHCH2CH3) group in this ion and related ones.
Enolization and oxidation: I. The reaction of 3‐hydroxy‐2‐butanone with ferricenium ions in an acidic medium
Authors: Lubach J. , Drenth W.
Published: September 2010

Oxidation of 3‐hydroxy‐2‐butanone, CH3COCHOHCH3 to 2,3‐butanedione, CH3COCOCH3, by ferricenium cations, Fe(C5H5)2⊕, has been studied in acidic 50 vol % aqueous ethanol. At ferricenium ion concentrations above 0.5 × 10−3 mole · l−1 the rate of reaction is independent of this concentration. Enolization is suggested to be rate determining. The influence of acid concentration and of oxygen has been studied.
C‐nitroso compounds. Part XII: Cis‐ and trans‐azodioxy compounds (dimeric nitroso compounds) by photochemical nitrosation of hydrocarbons with tert‐butyl nitrite
Authors: Mackor A. , de Boer Th. J.
Published: September 2010

The photochemical nitrosation of (cyclo)alkanes and alkylbenzenes, containing abstractable primary or secondary hydrogen atoms, with t‐butyl nitrite has been carried out at 0‐5°C using wavelengths around 400 nm. The main products are trans‐azodioxy compounds (trans‐dimeric nitroso compounds), derived from the solvent and the corresponding oximes in (total) yields, ranging from 55‐80%. At low temperature or with high‐energy light sources it is possible to isolate the cis‐compounds in low yields (up to 30%).
Structure and physical properties of aluminium alkoxides. Part II: Changes in physical properties of liquid aluminium isopropoxide during storage
Authors: Fieggen W. , Gerding H.
Published: September 2010

The density, refractive index, dielectric constant and viscosity of liquid aluminium isopropoxide have been studied.

From observations for the liquid at 25°, immediately after heating at 130° and cooling rapidly, an Onsager dipole moment of 1.7‐2.5 D is calculated.

During storage the physical properties change slowly. This confirms the occurrence of a molecular rearrangement reaction, which was inferred previously from molecular weight and NMR data. A further indication was obtained by the discovery of a second solid form of aluminium isopropoxide, which melts at 29.5°, whereas we have found also a form with melting point of about 137°, considerably higher than that for normal aluminium isopropoxide, 118°.

The rates of changes in density and viscosity have been measured at different temperatures, from which the activation energy for the rearrangement reaction is estimated to be about 12 kcal/mole.
The importance of orbital orientation as a rate‐controlling factor in intramolecular reactions of carbonium ions
Authors: Brouwer D. M. , Hogeveen H.
Published: September 2010

In carbonium ions the relative orientation of the vacantp‐orbital of the electron‐deficient carbon atom and the C‐H and C‐R bonds at the adjacent carbon atom (“orbital orientation”) is a very important factor for the rates of 1,2‐hydride and alkyl shifts and of cleavage of β C‐C bonds. A large number of examples of this effect can be found among the reactions of directly observable carbonium ions. In some cases it causes the rate of a 1,2‐shift or a β‐cleavage in a cyclic carbonium ion to be several orders of magnitude lower than in acyclic carbonium ions.
Mixed carboxylic anhydrides. Part VIII. Synthesis of aryl thiolformates
Authors: Bax P. C. , Stevens W.
Published: September 2010

An attractive synthesis of pure aryl thiolformates has been found in the base‐catalysed esterification of thiophenols with acetic formic anhydride or with a formic acid/acetic anhydride reaction mixture.
The trans‐1‐methylpentadienyl anion ‐ the charge‐repelling effect of the methyl group
Authors: Kloosterziel H. , van Drunen J. A. A.
Published: September 2010

The title anion and its rapid isomerization to the cis‐isomer have been observed with the aid of NMR spectroscopy. The difference in charge‐repelling capacity observed between the trans‐ and cis‐methyl groups is discussed.
Oxaheptatrienyl anion coupling constants and bond orders
Authors: Kloosterziel H.
Published: September 2010

Reaction of sorbic aldehyde with potassium amide in liquid‐ammonia yields, as revealed by NMR spectroscopy, the stable oxaheptatrienyl anion. A linear relation between coupling constants and bond orders is given.
Copper(II) alkyl isocyanide complexes
Authors: Stephany R. W. , Drenth W.
Published: September 2010

The first synthesis, isolation and characterization of four copper(II) isocyanide complexes are described, [Cu(CNR)4(H2O)2]X2 with R = tert‐butyl and 1,1,3,3‐tetramethylbutyl, and XClO4⊖ and BF4⊖.

Decomposition of these complexes leads to copper(I) derivatives. One of them could be characterized as [Cu(CN‐t‐C4H9)4](ClO4). Infrared, electron spin resonance, and some X‐ray data are provided.
The conformation of non‐aromatic ring compounds. Part 60. The crystal structure of 2‐p‐Chlorophenyl‐1,3‐dioxane
Authors: de Kok A. J. , Romers C.
Published: September 2010

Crystals of 2‐p‐chlorophenyl‐l,3‐dioxane are triclinic. The space group is P1¯. The unit cell containing two molecules has dimensions a = 9.708, b = 10.914, c = 4.740 Å, α = 90.7, β = 102.6 and γ = 103.1°.

Photographic X‐ray reflexion data (copper radiation) were recorded about two axes. The structure was solved by Patterson methods and refined by a least‐squares technique. The intramolecular bond distances and valency angles do not deviate from the expected values. The phenyl group is in equatorial orientation with respect to the chair‐shaped dioxane ring. The O‐C‐O part of the dioxane molecule is more puckered (average torsional angle 62.5°) than the corresponding cyclohexane ring; the values found for the torsional angles are in agreement with model studies and NMR measurements.
NMR spectra of some cyclic dienyl anions
Authors: Kloosterziel H. , van Drunen J. A. A.
Published: September 2010

The NMR spectra of the cyclohexadienyl anion 5 and of the cyclo‐octadienyl anion 7 have been studied. The strongly bent anion 7 shows at low temperatures reversible line broadening. At higher temperatures 7 electrocyclizes to the bicyclo[3.3.0]octenyl anion. It is concluded that in neither of these anions there is substantial 1,5 overlap (homoaromaticity).
Complexes with ligands containing nitrile groups.: Part VIII. Organic nitriles as ligand
Authors: Zuur A. P. , Reintjes A. H. L. , Groeneveld W. L.
Published: September 2010

A series of complexes of the type M2+(L)6(SbCl6−)2 is reported, in which M is Mg(II), Co(II), Ni(II), Cu(II) and Zn(II), and L (Ligand) is butyronitrile, isobutyronitrile, trimethylacetonitrile and benzonitrile. Ligand Field spectra have been investigated for the Co(II), Ni(II) and Cu(II) complexes, values for Dq and B are reported and compared with the values for methyl cyanide. In the infrared region shifts of the CN stretching frequencies are discussed.
The hydrogenation of benzene over supported platinum, palladium and nickel catalysts
Authors: Aben P. C. , Platteeuw J. C. , Stouthamer B.
Published: September 2010

The activity for the hydrogenation of benzene has been studied for supported platinum, palladium and nickel as a function of metal particle size and carrier. Metal crystallite sizes varied between 10 and 400 Å and silica, alumina, silica‐alumina and silica‐magnesia were used as supports. It has been found that the activity per exposed metal atom is independent of the metal crystallite size or of the support used. The hydrogenation activities per exposed metal atom at a temperature of 100°C and a hydrogen pressure of 5.6 atm are ranked as follows:

kpt: kNi: kPd = 18:7:1.

It is further shown that the activation energies observed experimentally for the various catalysts at a given set of conditions are predicted with a high degree of accuracy with the aid of the theory of absolute reaction rates, based on a resonable estimate of the number of exposed metal atoms per hydrogenation site.
Correlations between catalytic and thermodynamic parameters of transition metal Oxides
Authors: Sachtler W. M. H. , Dorgelo G. J. H. , Fahrenfort J. , Voorhoeve R. J. H.
Published: September 2010

The oxidation of benzaldehyde to benzoic acid with V2O5, SnO2‐promoted V2O5 and MnO2 as catalysts has been investigated. The reaction mechanism includes the following steps: dissociative chemisorption of benzaldehyde, yielding an asymmetric covalent benzoate complex with one oxygen atom of the sufrace, atomic rearrangement to the symmetric benzoate ion, desorption of benzoic acid and reoxidation of the catalyst surface by adsorption of oxygen. The activity of the oxides is found to be related to their ability to release oxygen. An antibatic relation between the Gibbs free energy of oxygen release and the catalytic activity is demonstrated. The action of the tin promoter in the mixed oxide catalyst is due to the loosening of the metal‐oxygen bond. A parallelism is suggested between the catalytic selectivity and the differential increase of the enthalpy of oxygen release with increasing degree of reduction.
Studies on cyclohexane derivatives. Part VIII: Preparation and mass spectra of the seven t‐butylcyclohexanecarboxylic acids
Authors: van Bekkum H. , van de Graaf B. , van Minnen‐Pathuis G. , Peters J. A. , Wepster B. M.
Published: September 2010

1‐t‐Butylcyclohexanecarboxylic acid (1) has been synthesized from t‐butyl‐cyclohexanols as well as from 2‐(1‐methylcyclohexyl)‐2‐propanol by the Koch ‐Haaf carboxylation. A side product in these preparations is 2‐methyl‐2‐(1‐methylcyclohexyl)propionic acid (5).

Details are given for the preparation of the cis‐ and trans‐isomers of 2‐, 3‐and 4‐t‐butylcyclohexanecarboxylic acid (cis‐ and trans‐2, 3 and 4) starting from the corresponding t‐butylbenzoic acids.

The t‐butylbenzoic acids and their methyl esters have been hydrogenated over transition metal catalysts at 25°. Palladium differs from platinum, rhodium and ruthenium by, in all cases, giving in excess the most stable isomer. In the hydrogenation of 2‐t‐butylbenzoic acid over rhodium desorbed 6‐t‐butyl‐1‐cyclohexene‐1‐carboxylic acid is shown to be the main source of the trans‐2 formed.

The mass spectra of 1 − 4 are presented and discussed. The mode of fragmentation of cis‐4 and cis‐3 was found to differ in a characteristic way from that of their trans‐isomers.
Isomerization, cracking and dehydrogenation of protonated mesityl oxide
Authors: Brouwer D. M. , van Doorn J. A.
Published: September 2010

Protonated mesityl oxide (1,3,3‐trimethyl‐1‐hydroxyallyl cation, 1) in strong acids has been found to give three reactions, resulting in a large variety of products depending on the acid used as the solvent.

(1) Isomerization, followed by cyclization, gives the 2,5‐dimethyltetrahydrofuryl cation, which is about 5 × 103 times stabler than 1. The isomerization, which proceeds via intermediate dications, is acid‐catalysed; its rate decreases strongly in the order 1: 1 HF‐SbF5 〉〉 9: 1 HF‐SbF5 〉 1: 1 FSO3H‐SbF5 〉〉〉 5: 1 FSO3H‐SbF5.

(2) In FSO3H‐SbF5, dehydrogenation with subsequent ring closure to give the 2,4‐dihydrofuryl cation.

(3) Cracking produces the acetyl cation and isobutene, which are formed by β‐scission of C‐protonated mesityl oxide. The isobutene fragment reacts further to give, depending on the acid and the rate at which it is formed, t‐butyl cation, or the disulfonic acids of isobutene, or products thereof, and alkylcyclopentenyl ions.

Rate constants of the three reactions in the different solvents have been measured. The 1‐ethyl‐3,3‐dimethyl‐1‐hydroxyallyl cation (2) reacts in a similar way, but different product selectivities are obtained.
Preparation and nmr spectra of 3‐alken‐1‐Ynylamines and 1,3,5‐Trienylamines
Authors: Galesloot W. G. , de Bie M. J. A. , Brandsma L. , Arens J. F.
Published: September 2010

Compounds of the type H2CCR1‐CC‐CH2‐N(C2H5)2(I), when treated with potassiumtert‐butoxide in dimethyl sulfoxide are converted predominantly into the 3‐alken‐1‐ynylamines H3C‐CR1CH‐CC‐N(C2H5)2(IV), while those of the type R2CH2‐CR3CH‐CC‐CH2‐N(C2H5)2(VI) yield 1,3,5‐trienylamines R2CHCR3‐CHCH‐CHCH‐N(C2H5)2(VIII). A discussion of the NMR parameters of the 1,3,5‐trienylamines is given.
Cleavage of α,β‐unsaturated Sulfides, Alkyl Cycloalkyl Sulfides AND Cycloalkanone Dialkyl Dithioacetals with Alkali Metals in liquid Ammonia
Authors: Brandsma L.
Published: September 2010

Unsaturated thiols having the system ‐C=C‐SH can be obtained by cleavage of the corresponding alkyl sulfides ‐C=C‐SR with alkali metals in liquid ammonia and acid hydrolysis after evaporation of the ammonia. Cycloalkanone dimethyl dithioacetals (CH2)nC(SCH3)2 give cycloalkanethiols (CH2)nC(H)(SH) (n = 2, 4, 5, 6) on treatment with 4 equivalents of alkali metal. Alkyl cycloalkyl sulfides (CH2)nC(H)(SR) (R = CH3 or C2H5) have been obtained by adding 2 equivalents of alkali metal to the dithioacetals (CH2)nC(SR)2. The cleavage reactions mentioned proceed with good to almost quantitative yields. The conversion of cycloalkyl ethyl sulfides and cycloalkanone diethyl dithioacetals with alkali metals is suitable for the preparation of the three‐ and six‐membered ring thiols but proceeds unsatisfactorily in the case of the five‐ and seven‐membered rings, cleavage between the ring and sulfur being the main reaction.
The photolysis of Cyclopropanecarbaldehyde at 254 nm in the presence of Neopentane, Cyclohexane and 2,3‐Dimethylbutane
Authors: Overwater J. J. I. , Cerfontain H.
Published: September 2010

Cyclopropanecarbaldehyde has been photolyzed in the gas phase with light of 254 nm, in the presence of each of the following hydrocarbons: neopentane, cyclohexane and 2,3‐dimethylbutane (biisopropyl). With increasing total pressure the quantum yields of the gaseous products carbon monoxide, ethene, propene and cyclopropane decrease. The decrease in the quantum yields of propene and ethene is explained in terms of collisional deactivation of vibration‐ally excited singlet excited cyclopropanecarbaldehyde.

The decrease in the quantum yield of cyclopropane with increasing total pressure is explained partly in terms of collisional deactivation of vibrationally excited triplet cyclopropanecarbaldehyde, and partly in terms of hydrogen abstraction by cyclopropyl radicals from the added hydrocarbon. With 2,3‐dimethylbutane as addendum the two mechanisms are of about equal importance, whereas with neopentane or cyclohexane the former mechanism is thought to predominate.
Photochemistry of non‐conjugated dienones: Irradiation oftrans‐α‐ionone
Authors: van Wageningen A. , de Boer Th. J.
Published: September 2010

After prolonged irradiation oftrans‐α‐ionone(I) in ethanol two new isomers IV and V (cf. Table I) can be isolated.
Conformation of non‐aromatic ring compounds. Part 64. NMR spectra and dipole moments of 2‐alkylthiotetrahydropyrans
Authors: de Hoog A. J. , Havinga E.
Published: September 2010

The conformational equilibrium in six 2‐alkylthiotetrahydropyrans is studied by means of dipole moment measurements and NMR spectroscopy. In these compounds the anomeric alkylthio group has, in general, a slight preference for the axial position. From the occurrence of a linear relationship between the squares of the dipole moments and vicinal coupling constants the conclusion follows that only one axial and one or two equatorial conformers are present in the equilibrium. A comparison is made with the conformation of the anomeric alkoxy group.
HO data and other properties of some hydrogen fluoride based solvents
Authors: Dalllnga G. , Gaaf J. , Mackor E. L.
Published: September 2010

The properties of a new acidic solvent system consisting of equimolar amounts of anhydrous hydrogen fluoride and oxygen‐containing components, such as alcohols, ether or acetic acid, are described. Through the addition of BF3 Hammett's acidity function, HO, can be varied between ‐ 1.4 and ‐ 7. These acids proved to be particularly useful for the study of the photochemistry of aromatic hydrocarbons.

Measurements of the Hammett function, HO, are reported for hydrogen fluoride containing sodium fluoride, water, ethanol and BF3.
An efficient nonenzymatic conversion of benzylpenicillin to 6‐aminopenicillanic acid
Authors: Weissenburger H. W. O. , van der Hoeven M. G.
Published: September 2010

An efficient procedure for the chemical conversion of benzylpenicillin to 6‐aminopenicillanic acid is described. The selective cleavage of the amide bond has been accomplished by treating the silyl ester of benzylpenicillin consecutively with phosphorus pentachloride, n‐butanol and water at low temperatures.
Association constants of the hexamethylbenzene‐1,3,5‐trinitrobenzene complex in various saturated hydrocarbon solvents
Authors: Foreman M. I. , Foster R.
Published: September 2010

From NMR chemical shift measurements, it is shown that the degree of association for the interaction between hexamethylbenzene and 1,3,5‐trinitro benzene in various saturated hydrocarbon solvents is dependent on the particular solvent, irrespective of the particular concentration scale used.
The alkylation of imine anions formation of enamines
Authors: Heiszwolf G. J. , Kloosterziel H.
Published: September 2010

The ambident anions derived from a number of imines have been alkylated using a variety of solvents and alkylating agents. Under reactive conditions enamines (N‐alkylation) are formed as the main products instead of the usually observed homologous imines (C‐alkylation). The influence of the type of imine, solvent and alkylating agent on the mode of alkylation is discussed.
Functionalized enamines. Part XI. Steric effects in α‐tetralone enamines
Authors: van der Vlugt F. A. , Verhoeven J. W. , Pandit U. K.
Published: September 2010

Synthesis of enamines 2a‐f, derived from α‐tetralones 1a, 1b, is described. Steric effects in the formation of these enamines and in the spectral properties of the corresponding 2‐substituted derivatives are discussed.
Koch‐Haaf carboxylations of tert‐alkyl substituted cycloalkanols
Authors: Peters J.A. , van Bekkum H.
Published: September 2010

Contrary to literature data 1‐isopropylcyclohexanol afforded both 1‐isopropylcyclohexanecarboxylic acid and 2‐cyclohexyl‐2‐methylpropanoic acid upon carboxylation by the method of Koch.

The Koch‐Haaf carboxylation of a number of tert‐alkyl substituted cycloalkane derivatives has been studied. Side reactions were suppressed by using the Haaf conditions with slow stirring of the reaction mixture.

tert‐Butylcyclohexanols afforded 1‐tert‐butylcyclohexanecarboxylic acid accompanied by 2‐methyl‐2‐(1‐methylcyclohexyl)propanoic acid. In the Koch‐Haaf reaction of 3‐tert‐butylcyclopentanol and 4‐tert‐butylcycloheptanol more complex rearrangements occurred. The main products were 1,2,2‐trimethylcyclohexanecarboxylic acid and 2‐cyclohexyl‐2,3‐dimethylbutanoic acid, respectively.

From the composition of the reaction products conclusions were drawn concerning the mechanisms of the rearrangements involved in these reactions. In some of the reactions protonated cyclopropane rings are proposed as intermediates.
The chemistry and fungicidal and phytotoxic properties of heterocyclic sulfonyl‐, sulfinyl‐, and thio‐methyl thiocyanates
Authors: Willems A.G.M. , Tempel A. , Hamminga D. , Stork B.
Published: September 2010

The synthesis of 38 compounds with structure RSOn‐CH2‐SCN, in which R is a heterocyclic radical and n = 0, 1, or 2, is described and their fungicidal and phytotoxic activities are discussed.