bluuebunny/crossref_metadata_2025_split huggingface dataset:
1,8‐Bis(phosphanyl)naphthalenes: 1,8‐Bis[(diethylamino)phosphanyl]‐naphthalene, 1,8‐Bis(dichlorophosphany)naphthalene, and 1, 3‐Dichloro‐2,‐3‐dihydro‐1,3‐dioxo‐2‐oxa‐1,3‐diphosphaphenalene
Authors: Karaçar Atilla , Thönnessen Holger , Jones Peter G. , Bartsch Rainer , Schmutzler Reinhard 
Published: July 2007

Abstract1.8‐dilithionaphthalene 1 reacted with bis(dimethylamino)‐chlorophosphane to form 1,8‐bis[(diethylamino)phosphanyl]‐naphthalene 2, whose structure was confirmed by X‐ray crystal structure analysis; there are two independent molecules, in which the P(NEt2)2 groups adopt an eclipsed conformation. Reaction of 2 with gaseous HCl gave in low yield 1,8‐bis‐(dichlorophosphanyl)naphthalene 3, which was characterized by 1H‐ and 31P‐NMR spectroscopy, mass spectrometry and elemental analysis. Attempted recrystallization of 3 led to oxidative hydrolysis which furnished 4, an anhydride of a bis(chlorophosphonic acid), whose structure was elucidated by X‐ray crystal structure analysis. The geometry of 4 reveals a relief of strain from the bis (aminophosphane) 2; the naphthalene groups are less distorted and the P atoms are displaced less far from the naphthalene best plane.
Enantioselective Catalysis. New Chiral Expanded Phosphanes Derived from Substituted Deltacyclenes
Authors: Brunner Henri , Reimer Alfred 
Published: July 2007

AbstractThe suitability of enantiomerically pure deltacyclenes as building blocks in the synthesis of expanded phosphanes was examined. Different substituted deltacyclenes were irradiated with diphenylphosphane and three bisphosphanyl derivatives. With these PH addition reactions, new chiral deltacyclane‐derived phosphorus ligands were synthesized. They were tested in the Rh‐catalyzed asymmetric hydrogenation of (Z)‐(ã)‐N‐acetamidocinnamic acid and in the Pd‐catalyzed asymmetric allylation of 1,5‐dimethylbarbituric acid.
Coordination Compounds of Coinage Metals with Vinylidenebis(diphenyl‐phosphane) and Its Disulfide and Their Reactivity towards Nucleophiles
Authors: Fernández Eduardo J. , Gimeno M. Concepción , Jones Peter G. , Laguna Antonio , López‐de‐Luzuriaga José M. , Olmos Elena 
Published: July 2007

AbstractVinylidenebis(diphenylphosphane) reacts with gold(I) or gold(III) compounds to give dinuclear {[{Au(C6F5)]2[(PPh2)2CCH2{] or [Au{PPh2C(CH2)Ph2P)]2(ClO4)2] or mononuclear complexes ([Au(C6F5)3(PPh2C(CH2)Ph2P)]}, respectively. The latter reacts with gold(I) or silver(I) compounds to afford dinuclear [[Au(C6F5)3[PPh2C(CH2)Ph2P}AuX], XCl or C6F5) or trinuclear species {[{Au(C6F5)3{PPh2C(CH2)Ph2P{]2M]ClO4, MAu or Ag}. No addition of nucleophiles to the CC double bond is observed in these complexes, which contain the diphosphane acting as bridging or monodentate ligand. (SPPh2)2CCH2 reacts with AgClO4 to give [Ag{SPPh2C(CH2)Ph2PS}]2‐(ClO4)2or[Ag[PPh2C(CH2)Ph2P]2]ClO4. The crystal structure of [Au(C6F5)3{PPh2C(CH2)Ph2P}Au(C6F5)] has been established by X‐ray crystallography, and confirms the expected square planar and linear geometry for the Au111 and Au1 centres, respectively.
Unusual Dinuclear Hydridorhodium(III) Complexes Containing Bulky Phosphanyl(stibanyl)methanes as Chelating Ligands
Authors: Manger Matthias , Gevert Olaf , Werner Helmut 
Published: July 2007

AbstractThe mononuclear starting materials [Rh(η4‐C8H12)(k2‐P,Sb‐iPr2PCH2SbR2)]PF6 (la, b) react with CF3CO2H in the presence of H2 to give the dinuclear hydridorhodium(II1) complexes [{RhH(k2‐P,Sb‐iPr2PCH2SbR2)]PF6 (2a, b) in almost quantitative yield. The X‐ray crystal structural analysis of 2b (R = tBu) reveals a distorted octahedral geometry around the two metal centers with the two phosphanyl(stibanyl)methanes in a chelating and the two trifluoracetate ligands in a bridging coordination mode.
X‐ray and Solution Structure of Inosine 5' ‐Monophosphate Coordinated to (Ethylenediamine)palladium(II). —the Importance of Intramolecular Hydrogen Bonding
Authors: Rau Tobias , Van Eldik Rudi 
Published: July 2007

AbstractThe compound [Pd(en)(5′‐IMP‐N7)2].11 H2O, where 5′‐IMP = inosine 5′‐monophosphate, crystallizes in the tetragonal space group P4322 with the unit cell parameters: a = b = 12.060(5) and c = 28.510(5) Å, V = 4147(3) Å3, Z = 4. A head‐to‐tail orientation with A configuration is observed for the nucleotides which are coordinated through the N(7) positions such that d[Pd‐N(7)] = 2.053(8) Å. The sugar moieties exhibitantiorientations toward the purine bases while their pukkers adopt C(3)′‐endoconformation. The overall conformation about the phosphate backbone is gauche+. Intramolecular hydrogen bonding is observed between the phosphates and the NH groups of the en ligand with a donor‐acceptor distance of 2.88 Å. The coordination mode of the solid‐state structure is shown to be identical to that observed by1H‐NMR spectroscopy in solution under slightly acidic conditions, where the N (l) positions of the nucleotides are protonated. The results are discussed in reference to closely related systems reported in the literature with emphasis on the importance of hydrogen bonding in such complexes.
A Series of Carbonyl‐, Olefin‐, Alkyne‐, Hydrido‐, and Vinyliridium Complexes Containing Bulky Bifunctional Phosphanes iPr2PCH2X as Ligands
Authors: Steinert Paul , Werner Helmut 
Published: July 2007

AbstractEtheneiridium(I) complexes of the general composition trans‐[IrCl(C2H4)L2] [L = iPr2PCH2CO2Me (2a), iPr2PCH2CO2Et (2b), iPr2P(CH2)3NMe2 (2c)] have been prepared either from [IrClL2] (3) or [IrCl(C2H4)2]2 (7) as starting materials. The corresponding carbonyl derivatives trans‐[IrCl(CO)L2] (6, 10, 11) are obtained along similar routes. Photolysis of trans‐[IrCl(C2H4)L2] (L = 2a, 2b) leads, by intramolecular C–H activation, to the formation of the octahedral hydrido(vinyl)iridium(III) compounds [IrHCl(CHCH2)(k‐L)(k2‐L)] (16, 17), which are highly fluctional in solution. Carbonyl(hydrido)(vinyl) complexes are accessible either from 16 or 17 and CO, or from trans‐[IrCl(C2H4)L2] (L = 2a) and the propargylic alcohol HCCCH(Ph)OH, respectively. Treatment of 3 or the corresponding dihydrido compound [IrH2ClL2] (4) with methyl vinyl ketone or methyl acrylate also yields hydrido(vinyl)iridium(III) complexes [IrHCl(CHCHX)L2] [X = C(=O)Me (18), C(=O)OMe (19)], in which instead of the CO function of the phosphanyl ester the carbonyl group of the vinylic moiety is coordinated to the metal. The reaction of 16 (L = 2a) with terminal alkynes HCCR (R = Ph, CO2Me) affords the structurally related alkynyl(hydrido)iridium(III) compounds [IrHCl(CCR)(k‐L)(k2‐L)] (28, 29), while from 16 and internal alkynes RCCR) the iridium(I) complexes trans‐[IrCl1(RCCR)L2] (30, 31) are obtained, Stepwise treatment of trans‐[IrCl(RCCR)L2] (6: L = 2a) with NaN(SiMe3)2, (ii) H2O, and (iii) HCl leads, in the coordination sphere of the metal center, to a conversion of iPr2PCH2CO2Me to iPr2PCH2CO2H via the isolated phosphanylenolate and phosphanylacetate complexes 32 and 33 as intermediates.
Reversible Rearrangements of Chlorophosphane‐Dichlorogermylene Ylides to Trichlorogermylphosphanes — Structure Determination of a Tetranuclear Bis(chlorophosphane)bis(trichlorogermylphosphane) Silver Bromide Complex
Authors: Mont Wolf‐Walther Du , Karnop Michael , Mahnke Jens , Martens Reiner , Druckenbrodt Christian , Jeske Jörg , Jones Peter G. 
Published: July 2007

AbstractChlorophosphanes RR'PCl (1a: R,R' = 1b: R = tBu, R' = iPr, 1c: R = iPr, R' = Et2N, 1d: R = Et2N react with the dichlorogermylene dioxane complex 2 furnishing trichlorogermylphosphanes RR'PGeCl3 4a–d. In the cases of 1c/4c and 1d/4d the insertion reaction remain incomplete; similarly, 4a always contains, shortly after isolation in pure state, small amounts of 1a that can be detected by NMR. A provided by the reaction of trichlorosilylphosphane tBu(Et2N)PSiCl3 (5d) with GeCl4. The alkyl(dialkylamino) trichlorogermylphosphane 4d exists only in an equilibrium with chlorophosphane 1d, which coordinates GeCl2 leading to the dichlorogermylene complex 3d. A 1:1 mixture of 4a with 1a is formed by the novel cleavage (“chlorogermylation”) of the P–P bond of tetraisopropyldiphosphane with germanium tetrachloride. Di‐tert‐butyl(trichlorogermyl)phosphane 4e (R, R' = tBu) reacts with silver bromide providing a crystalline silver complex 7. A structure determination by X‐ray diffraction reveals that 7 is [Ag4Br4(tBu2PCl)2(tBu2PGeCl3)2]. 2C7H8. Two of the Ag atoms of the cubane‐like (AgBr)4 core of 7 are coordinated by chlorophosphane 1e, the other two by trichlorogermylphosphane 4e.
Investigation of Host‐Guest Interactions between Rubidium Salts and N‐(Arylazoalkenoyl)azacoronands by Solid‐State NMR Spectroscopy
Authors: Costisella Burkhard , Müller Dirk , Baumann Hendrik 
Published: July 2007

AbstractRubidium salts with N‐(Arylazoalkenoyl)azacoronands (2a–c), were investigated using 87Rb and 13C solid‐state NMR spectroscopy. From the NMR results it is concluded that there is a host‐gust interaction. This suggests that the rubidium and ammonium ions, respectively, are incorporated into the cavity between the coronand and the chromophore.
Chlorides and Acetylacetonates of Transition Metals as Catalysts for the Oxidation of 1‐Indanol by Sodium Percarbonate
Authors: Aït‐Mohand Samia , Muzart Jacques , Lunak Stanislav 
Published: July 2007

AbstractThe screening of metal chlorides and metal acetylacetonates as catalysts for the oxidation of 1‐indanol by sodium percarbonate (at reflux in 1,2‐dichloroethane in the presence of small amounts of Adogen 464) has been carried out. The efficiency of the process depended on the nature of the transition metal and its oxidation state but, except for iron, was not greatly influenced by the nature of the ligands. Good conversions and yields have been obtained using PdCl2, RhCl3, RuCl3 and, particularly, MoO2(acac)2 as catalysts.
A New Route to Sila‐ and Phosphaheterocycles: Nucleophilic Aminomethylation
Authors: Karsch Hans H. , Schreiber Kai A. , Herker Martin 
Published: July 2007

AbstractThe aminals tetramethylmethylenediamine (TMMDA) la, dicyclohexyldimethylmethylenediamine (CMMDA) lb, and di‐isopropyldimethylmethylenediamine (IMMDA) lc are doubly metalated by LitBu to give LiCH2N(R)CH2N(R)CH2Li [2a: R = Me, 2b: R = Cy (Cy = cyclohexyl), 2c: R = iPr], which precipitate out of pentane as highly pyrophoric substances. Deuteration confirms N‐methyl metalation exclusively. A series of aminomethylation reactions were performed by means of the doubly lithiated aminals 2a‐c. The reactions of 2a‐c with monochlorosilanes yield the silylated species R′3SiCH2MN(R)CH2N(R)CH2SiR′3 (3a: R′= Me, R == Me; 3b: R′ == Me, R == Cy; 3c: R′= Me, R = iPr 4: R′= Ph, R = Me, see Scheme 2). The use of dichlorosilanes lead to six‐membered heterocycles 6a‐6d. 6a is transferred into a mono quarternary ammonium salt 7 by methylation with MeI. The spirocycle 8 is obtained from SiCl4 and two equivalents of 2a. Similarly, several substituted 1,3‐diaza‐5‐phosphacyclohexanes 9a‐e (R1 = Me, Ph, NPh2, NCy2, see Scheme 3) are synthesized by the reaction of dichlorophosphanes R1PC2, with 2a and 2b, respectively. Oxidation of 9d with sulfur yields 12a, which is characterized by X‐ray structure determination.
Kinetics and Mechanism of Substitution Reactions of cis‐[PtMe2(dmso)2] with Pyridine
Authors: Schmüling Michael , van Eldik Rudi 
Published: July 2007

AbstractThe substitution reactions of cis‐[PtMe,(dmso),] with pyridine (py) to produce cis‐[PtMe2py2] in toluene proceeds in two steps. In the absence of added dimethylsulfoxide (dmso), these steps can not be separated due to the rate constants being very similar. In the presence of added dmso, the rate of the first step, the formation of the monopyridine complex is retarded, which is indicative of a dissociative mechanism. A parallel associative reaction path with pyridine could also be observed. This pathway is independent of the concentration of added dmso. Above a 40‐fold excess of dmso, the dissociative pathway is suppressed and only the associative reaction occurs. A plot of Kobs vs the pyridine concentration for this pathway is linear at low [py], but shows a saturation at high [py]. This suggests that the reaction occurs via the formation of a precursor‐complex, for which the formation constant was found to be 0.32 · 0.03 M−1. The volume of activation at a high pyridine concentration is −11.4 · 0.8 cm3 mol−1, which indicates that the ligand interchange process is of the associative type. The second step, the formation of the bispyridine complex, can clearly be separated from the first reaction step. This step occurs via a dissociative mechanism, as demonstrated by the decrease in kobs with increasing pyridine concentration. The dissociation of dmso was characterized by a rate constant of (8.1 · 0.9).10−45−1 at 25°C, ·H = 116 ·9 kJ mol−1 and AS. = 86 · 29 JK−1 mol−1. At higher pyridine concentrations evidence for a parallel associative reaction was found, for which the rate constant is (1.3 · 0.2).10−3 M−1S−1 25°C. The results are discussed in reference to available literature data.
An Ylide‐Substituted Tetraphosphene, Cyclotetraphosphane, and Bicyclotetraphosphane
Authors: Schrödel Haus‐Peter , Nöth Heinrich , Schmidt‐Amelunxen Martin , Schoeller Wolfgang W. , Schmidpeter Alfred 
Published: July 2007

AbstractThe reaction of two specific ylidyl dichlorophosphanes, Ph3P=CR‐PCl2, with P(SiMe3)3 yields the ylidyl trimethylsilyl diphosphenes Ph3P=CR.P=P‐SiMe3 as primary products which form two different types of dimers: the cyclotetraphosphane 9 (R = SiMe3), and the tetraphosphene 10 (R = 2,6‐Cl, 2,/C6H3). The latter compound is readily converted to the bis(ylidyl)biocyclotetraphosphane 11. The molecular structures of 9 and 11 allow a strong transanular interaction between teh ylide‐substituted phosphorus atoms, which results in very large two‐bond coupling constants (2Jpp = 184 and 332 Hz respectively). The central P bond in 11 is relatively long (220.7 pm); quantum chemical calculations show the lengthening to be a consequence of the perpendicular orientation of the ylidic donor p‐orbital.
Preparation, Properties, and Reactions of Metal‐Containing Heterocycles, XCVII – Differently Substituted Benzomolybdacrown Ethers and Their Capability of Including Alkali Metal Cations
Authors: Lindner Ekkehard , Günther Matthias F. , Mayer Hermann A. , Fawzi Raid , Steimann Manfred 
Published: July 2007

AbstractThe reaction of the diphosphanes 2a‐i with (OC)4Mo(nbd) under high dilution conditions affords the mononuclear benzomolybdacrown ethers cis‐(OC)4Mo{1,2‐, 1,3‐, 1,4‐[PH2PCH2(CH2OCH2)πCH2]2C6H4‐P, P′] (3a‐i) (n = 1, 2). On the basis of the 31P nucleus the inclusion behavior of the molydacycles 3a‐i toward the alkali metal salts LiBF4 and NaBPh4 was investigated with the aid of a NMR titration technique by using the program EQNMR. Only 3dshows an interaction with the alkali metal cation Na+ forming a 1:1 and 2:1 complex (3d/cation) while no interaction with Li+ could be detected. The molecular structures of 3a and 3d were elucidated by X‐ray structural analyses. Complexes 3a and 3d crystallize in the monoclinic space groups P21/c and P21/n with Z = 8 and 4, respectively.
Quantitative structure–activity relationship of hydroxyl‐substituent Schiff bases in radical‐induced hemolysis of human erythrocytes
Authors: Tang You‐Zhi , Liu Zai‐Qun 
Published: July 2007

AbstractThe major objective of this work was to explore the quantitative structure–activity relationship (QSAR) of hydroxyl‐substituent Schiff bases in protecting human erythrocytes against 2,2′‐azobis(2‐amidinopropane hydrochloride) (AAPH)‐ induced hemolysis, in which 10 Schiff bases including 4‐phenyliminomethylphenol (PIH); 4‐((4‐hydroxybenzylidene) amino)phenol (PAH); 2‐methoxy‐4‐((4‐hydroxyphenylimino)methyl)phenol (PMH); 4‐((furan‐2‐ylmethylene)amino) phenol (FAH); 4‐((4‐N,N‐dimethylaminobenzylidene)amino)phenol (PDH); 2‐((4‐N,N‐dimethylaminobenzylidene)amino) phenol (ODH); 2‐(naphthalene‐1‐yliminomethyl)phenol (NAH); 2‐(benzyliminomethyl)phenol (BPH); 1,4‐di((2‐hydroxyphenylimino) methyl)benzene (DOH); 1,4‐di((4‐hydroxyphenylimino)methyl)benzene DPH, were available for this in vitro experimental system. The results revealed that the radical‐scavenging activity of the OH attached to the para position of methylene in Schiff base was much lower than that attached to the ortho position of the N atom. The large conjugate system and low steric hindrance in the framework of Schiff base benefit the Schiff base to trap radicals. Meanwhile, since a Schiff base, even without any substituent, can also play an antioxidative role in this experimental system, the QSAR results suggest that hydroxyl‐substituent Schiff bases are potential drugs in the treatment of radical‐related diseases, and provide more information for designing novel drugs. Copyright © 2007 John Wiley & Sons, Ltd.
The Use of Non‐natural Nucleotides to Probe Template‐Independent DNA Synthesis
Authors: Berdis Anthony J. , McCutcheon David 
Published: July 2007

AbstractThe vast majority of DNA polymerases use the complementary templating strand of DNA to guide each nucleotide incorporation. There are instances, however, in which polymerases can efficiently incorporate nucleotides in the absence of templating information. This process, known as translesion DNA synthesis, can alter the proper genetic code of an organism. To further elucidate the mechanism of template‐independent DNA synthesis, we monitored the incorporation of various nucleotides at the “blunt‐end” of duplex DNA by the high‐fidelity bacteriophage T4 DNA polymerase. Although natural nucleotides are not incorporated at the blunt‐end, a limited subset of non‐natural indolyl analogues containing extensive π‐electron surface areas are efficiently utilized by the T4 DNA polymerase. These analogues possess high binding affinities that are remarkably similar to those measured during incorporation opposite an abasic site. In contrast, the kpol values are significantly lower during blunt‐end extension when compared to incorporation opposite an abasic site. These kinetic differences suggest that the single‐stranded region of the DNA template plays an important role during polymerization through stacking interactions with downstream bases, interactions with key amino acid residues, or both. In addition, we demonstrate that terminal deoxynucleotide transferase, a template‐independent enzyme, can efficiently incorporate many of these non‐natural nucleotides. However, that this unique polymerase cannot extend large, bulky non‐natural nucleotides suggests that elongation is limited by steric constraints imposed by structural features present within the polymerase. Regardless, the kinetic data obtained from using either DNA polymerase indicate that template‐independent synthesis can occur without the contributions of hydrogen‐bonding interactions and suggest that π‐electron interactions play an important role in polymerization efficiency when templating information is not present.
LaMnO3 Perovskite Supported Noble Metal Catalysts for the Total Oxidation of Methane
Authors: Giebeler L. , Kießling D. , Wendt G. 
Published: July 2007

AbstractTwo series of LaMnO3 supported noble metal (Pt, Pd, Rh) catalysts prepared by the citrate method and calcined in air at 600 and 800 °C, respectively, were investigated. The catalysts resulting from method A were prepared by simultaneous incorporation of the noble metals during perovskite preparation and those following method B were generated by impregnation of the calcined perovskites with the noble metal compounds. The noble metals form solid solutions with the perovskite lattice. Reduction of the catalysts with hydrogen prior to the catalytic reaction led to a significant enhancement of the catalytic activity. During the catalytic reaction, the noble metal clusters are partially transformed to highly dispersed noble metal oxides or nonstoichiometric noble metal oxide phases, which are the catalytically active phases for the total oxidation of methane. The best results were obtained with the Pd containing catalysts prepared by method B.
Predicting the Displacement of Yoghurt by Water in a Pipe Using CFD
Authors: Regner M. , Henningsson M. , Wiklund J. , Östergren K. , Trägårdh C. 
Published: July 2007

AbstractA numerical scheme based on the volume of fluid (VOF) method for predicting the displacement of one liquid by another has been verified versus electrical resistance tomography (ERT) and ultrasonic velocity profile (UVP) measurements for the displacement of yoghurt by water. The scheme using the VOF method predicts the skewed phase distribution as measured using ERT and the global structure of the velocity profile as measured using UVP. The phase distribution using the VOF method was compared with the results using the species transport model which allows for mixing between the phases. The species transport model was found to be less suitable for predicting the displacement of yoghurt by water since the turbulence model was unable to accurately predict the turbulent viscosity in the mixing zone between yoghurt and water, which resulted in a too high rate of mixing.
Vapor Condensation Heat Transfer in a Thermoplate Heat Exchanger
Authors: Mitrovic J. , Peterson R. 
Published: July 2007

AbstractThe heat transfer and pressure drop in a thermoplate heat exchanger operating as a condenser have been investigated experimentally. In order to separate the heat transfer resistances in the condensation process, the single phase forced convection has been studied using distilled water and Marlotherm oil in the thermoplate and correlations developed for the Nusselt number and the friction factor. For the condensation experiments, an apparatus has been constructed comprising two identical condensers composed of the same thermoplate type as employed in the single phase experiments. Isopropanol is used as a test fluid at pressures below atmospheric pressure. The heat transfer resistances in the condensation experiments are separated and expressions for the condensation heat transfer and pressure drop are developed with the aid of the results obtained in the single phase studies.
The Concept of Protobranching and Its Many Paradigm Shifting Implications for Energy Evaluations
Authors: Wodrich Matthew D. , Wannere Chaitanya S. , Mo Yirong , Jarowski Peter D. , Houk Kendall N. , Schleyer Paul von Ragué 
Published: July 2007

AbstractBranched alkanes like isobutane and neopentane are more stable than their straight chain isomers, n‐butane and n‐pentane (by 2 and 5 kcal mol−1, respectively). Electron correlation is largely responsible. Branched alkanes have a greater number of net attractive 1,3‐alkyl–alkyl group interactions, there are three such stabilizing 1,3 “protobranching” dispositions in isobutane, but only two in n‐butane. Neopentane has six protobranches but n‐pentane only three. Propane has one protobranch and is stabilized appreciably, by 2.8 kcal mol−1, relative to methane and ethane. This value per protobranch also applies to the n‐alkanes and cyclohexane. Consequently, energy evaluations employing alkane reference standards, for example, of small ring strain and stabilizations due to conjugation, hyperconjugation, and aromaticity, should be corrected for protobranching, for example, by employing Pople's isodesmic bond separation reaction method. This reduces the ring strain of cyclopropane to 19.2 from the conventional 27.7 kcal mol−1, while the stabilization energies of alkenes and alkynes due to hyperconjugation (5.5 and 7.7 kcal mol−1 for propene and propyne) and conjugation (14.8 and 27.1 kcal mol−1 for butadiene and butadiyne) are considerably larger than the traditional estimates. Widely diverging literature evaluations of benzene resonance energy all give ≈65 kcal mol−1 after adjusting for conjugation, hyperconjugation, and protobranching “contaminations.” The BLW (block localized wavefunction) method, which localizes π bonds and precludes their interactions, largely confirms these stabilization estimates for hyperconjugation, conjugation, and aromaticity. Protobranching is seriously underestimated by theoretical computations at the HF and most DFT levels, which do not account for electron correlation satisfactorily. Such levels give bond separation energies, which can differ greatly from experimental values.