bluuebunny/crossref_metadata_2025_split huggingface dataset:
Micellar Accelerated Reduction of Ethylenediaminetetraacetatocobaltate(III) by 1-Benzyl-1,4-dihydronicotinamide
Authors: Yamashita Kohichi , Chiba Masahiro , Ishida Hitoshi , Ohkubo Katsutoshi 
Published: July 2006

Abstract
The electrostatic and hydrophobic effects of ionic micelles on the reduction of ethylenediaminetetraacetato cobaltate(III) ([Co(edta)]−) by 1-benzyl-1,4-dihydronicotinamide (BNAH) were investigated with dodecyltrimethylammonium chloride (DTAC) and/or sodium dodecyl sulfate (SDS). Cationic DTAC accelerated the reduction of [Co(edta)]−, while anionic SDS retarded the reaction. The micellar effects of DTAC on the present reaction at 30°C were kinetically analyzed by using the ion-exchange model and the Berezin’s approach: the evaluated rate constant, (1.0±0.1–1.1±0.4)×10−4 mol−1 dm3 s−1, for the micellar-phase reaction was ten times smaller than that, 1.46×10−3 mol−1 dm3 s−1, for the aqueous-phase one. This fact was well-explained by the electron-transfer rate constant calculated with the experimentally determined redox potentials of BNAH and [Co(edta)]−. The cationic DTAC micelles, however, resulted in considerably larger value (3.58×10−3 mol−1 dm3 s−1) of overall reaction rate constant than that (1.46×10−3 mol−1 dm3 s−1) of nonmicellar one, because the apparent concentrations of the reactants in the micellar phase increased remarkably by condensation of BNAH and [Co(edta)]− to the micelles through the hydrophobic interaction and the electrostatic interaction, respectively.
Oxidative Cleavage of Diselenide by m-Nitrobenzenesulfonyl Peroxide. Novel Method for the Electrophilic Benzeneselenenylations of Olefins and Aromatic Rings
Authors: Yoshida Masato , Sasage Shuichi , Kawamura Kyoko , Suzuki Takashi , Kamigata Nobumasa 
Published: July 2006

Abstract
Diphenyl diselenide was found to be readily converted into benzeneselenenyl m-nitrobenzenesulfonate (PhSeOSO2C6H4NO2-m) by treating with m-nitrobenzenesulfonyl peroxide. When the selenenyl sulfonate thus formed was allowed to react in situ with olefins, such as cyclohexene, 1-octene, or styrene, in the presence of various nucleophiles, the adducts of benzeneselenenyl group and a nucleophile were obtained. As the nucleophiles water, methanol, acetic acid, phenol, and anisole could be employed; oxyselenenylated ((Remark: Graphics omitted.) : R=H, Me, Ac, and Ph) and arylselenenylated ((Remark: Graphics omitted.) : R=H and Me) adducts were afforded. Phenol gave oxyselenenylated products in cyclohexene or 1-octene and arylselenenylated products in styrene. Efficient intramolecular cyclizations of unsaturated alcohols and carboxylic acids were similarly performed by the selenenyl sulfonate to afford corresponding benzeneselenenylated cyclic ethers and lactones. The selenenyl sulfonate was also found to be a highly reactive benzeneselenenylating reagent for aromatic rings, such as anisole, phenol, acetanilide, toluene, and benzene.
Aromatic Nucleophilic Substitution of Halobenzenes with Amines under High Pressure
Authors: Ibata Toshikazu , Isogami Yasushi , Toyoda Jiro 
Published: July 2006

Abstract
The nucleophilic substitution reactions of aromatic halides having electron-attracting groups on ortho or para position with various primary and secondary amines were accelerated by high pressure to give the corresponding N-substituted anilines in high yields. The bulkiness of amines affects its reactivity to lower the yields of the products. Although the secondary amines are usually less reactive than primary amines, cyclic secondary amines such as morpholine, piperidine, and pyrrolidine were found very reactive. 1,4-Diazabicyclo[2.2.2]octane and quinuclidine gave N-quaternary ammonium halides in high yields in contrast to the low reactivity of acyclic tertiary amines. Dichloro- and trichloro-nitrobenzenes also react with diethylamine, pyrrolidine, and morpholine to give mono-, di-, and trisubstitution products depending upon the amount of amine and the position of nitro group in these chlorides.
Exciplex Formation between Perylene and N,N-Dimethylaniline in a Ternary Inclusion Compound with γ-Cyclodextrin in H2O–Ethanol (7 : 3) Mixture
Authors: Hamai Sanyo 
Published: July 2006

Abstract
Inclusion compounds in the system of γ-cyclodextrin (γ-CD)-N,N-dimethylaniline (DMA)-perylene (Pe) have been studied in an H2O–ethanol (7 : 3) mixture by means of absorption and fluorescence spectral measurements. A ternary 1 : 1 : 1 inclusion compound of γ-CD–ethanol–Pe is formed by the addition of γ-CD to an H2O–ethanol solution of Pe. In the presence of γ-CD, a further addition of DMA results in the formation of a γ-CD–DMA–Pe inclusion compound followed by association with a 1 : 1 γ-CD–DMA inclusion compound to form a ternary 2 : 2 : 1 inclusion compound of γ-CD–DMA–Pe. The exciplex fluorescence of Pe–DMA within the γ-CD cavity has been observed from the ternary inclusion compound. Equilibrium constants for the formation of these inclusion compounds have been evaluated.
Ion-Exchange Reaction on Cubic Ammonium Molybdate in Acidic and Alkaline Media–Exchange of Structural NEU4+
Authors: Khan Abdul Jabbar , Abe Mitsuo , Kanzaki Yasushi , Tsuji Masamichi 
Published: July 2006

Abstract
The alkali metal ion exchange reaction on cubic ammonium molybdate (CAM) cation exchanger was studied in acidic as well as alkaline media. The ion-exchange reaction and TPD-Mass thermogram of CAM indicated the presence of structural NH4+ as interstitial solid solution. The stuctural NH4+ in the H+ form of CAM (H-CAM) was efficiently exchanged with K+ as compared with other alkali metal ions in the equilibrated solutions. The exchanger was observed to be stable in acid medium, however structural transformations were observed at high pH. The presence of K+ and Cs+ at high pH could act as “Structure Building Ions” for CAM or H-CAM.
Solvent Extraction of Dansyl-Amino Acid Anions by Dicationic Extractants
Authors: Ohki Akira , Dohmitsu Hiroyuki , Maeda Shigeru 
Published: July 2006

Abstract
The extraction of dansyl-amino acid anions from an alkaline aqueous medium was studied by the use of dicationic anion-exchange extractants, polymethylenebis(trioctylphosphonium)s (abbreviated as CnBPs; n=2–12). As for the extraction of dianionic species, such as dansyl-aspartic acid anion (Dns-Asp2−) and dansyl-glutamic acid anion (Dns-Glu2−), the dicationic extractants were greatly superior to a monocationic extractant, butyltrioctylphosphonium (BuMP). However, regarding the extraction of monoanionic species, such as dansyl-serine anion, dansyl-phenylalanine anion, and dansyl-valine anion, the extraction abilities of the dicationic extractants and the monocationic extractant were similar to one another. The extraction ability of dicationic extractants was remarkably dependent on the length of their bridge-chain, which connects the two ionic centers. For extractants having short bridge-chain (C2BP–C4BP), Dns-Asp2− was more extracted than Dns-Glu2−. On the contrary, for extractants with long bridge-chain (C8BP–C12BP) , Dns-Glu2− was more extracted than Dns-Asp2−. The solvent effect on the extraction of Dns-Asp2− and Dns-Glu2− was also studied.
Temperature Effect on the Adsorption and Micelle Formation of Aqueous Dodecyltrimethylammonium Chloride–Hexane System
Authors: Abe Koji , Kajiwara Ichiro , Ikeda Norihiro , Aratono Makoto , Motomura Kinsi 
Published: July 2006

Abstract
The adsorption at water/hexane interface and micelle formation of dodecyltrimethylammonium chloride (DTAC) were studied by measuring its interfacial tension as a function of temperature under atmospheric pressure at various concentrations around the critical micelle concentration (cmc). By applying the thermodynamic equations developed previously, the entropy and energy changes associated with the adsorption from monomeric and micellar states were estimated and compared with those of the DTAC solution–air system. It was found that the entropy and energy of the adsorbed film of DTAC are remarkably depressed by the coexistent hexane phase. This finding explains the positive entropy change associated with the adsorption of DTAC at water/air interface.
Electrochemical Studies of Poly(mercaptohydroquinone) and Poly(mercapto-p-benzoquinone) Films Prepared by Electrochemical Polymerization. V. Spectroelectrochemistry of Ten pH Indicators in the Film
Authors: Arai Gorou , Imai Kenji , Tanaka Ken-ichiro , Yasumori Iwao 
Published: July 2006

Abstract
The electroconductive, almost colorless and transparent poly(mercaptohydroquinone/mercapto-p-benzoquinone) film, prepared by electropolymerization of mercaptohydroquinone on an SnO2/glass electrode, was impregnated with a pH indicator. The film exhibited a clear electrochromic behavior arising from proton release/consumption within the film by electrooxidation/reduction, as verified by spectroelectrochemical measurements. For ten different pH indicators examined, such a color change could be well repeated over a long-term continuous experiment by use of potential steps.
Hydrogenation of 1,3-Butadiene over CaO Catalyst Treated with Methanol
Authors: Matsuda Tsuneo , Sugimoto Masatoshi , Yoshiara Hiroshi 
Published: July 2006

Abstract
When calcium oxide was treated with methanol at low temperature, calcium methoxides i.e., calcium dimethoxide and, calcium hydroxide methoxide, could be easily formed. The catalyst produced by the thermal decomposition of these compounds exhibited remarkably high activity to the hydrogenation of 1,3-butadiene. With the aim to investigate the cause of the high activity, two other calcium oxide catalysts were used for a comparison. The cause was ascribed to the formation of a large amount of electron-donating sites, including both basic ones and those with a high surface area.
Synthesis and Properties of Gramicidin S Analogs Containing d-Lys Residue in Place of Orn Residue
Authors: Tamaki Makoto , Akabori Sadatoshi , Muramatsu Ichiro 
Published: July 2006

Abstract
[l-Lys2,2′]-gramicidin S has been known to possess the same type activity and conformation as that of gramicidin S. The d-isomer of the Lys residue, instead of the Orn residue, was introduced to gramicidin S in order to investigate the contribution of the configurations of the Orn residue in gramicidin S to its activity and conformation. [d-Lys2,2′]- and [d-Lys2, l-Lys2′]-gramicidin S were synthesized by a liquid-phase method. The CD spectra of these analogs showed a pattern similar to that of gramicidin S, suggesting that the conformation of these analogs at the β-turn parts around the d-Phe-Pro sequence resemble that of gramicidin S. These analogs have either a weak or no activity against the Gram-positive microorganisms tested, indicating the importance of the configuration of the Orn residue in gramicidin S for exhibiting strong activity.
Enhanced Enantioselectivity of the Lipase-Catalyzed Hydrolysis by the Addition of a Catalytic Amount of an Amino Alcohol
Authors: Itoh Toshiyuki , Ohira Eri , Takagi Yumiko , Nishiyama Shigenori , Nakamura Kaoru 
Published: July 2006

Abstract
l-Methioninol (l-MetOH) was discovered to be an effective additive for improving the enantioselectivity of lipase-catalyzed hydrolysis. It was found that l-MetOH accelerated the enzyme-catalyzed hydrolysis of (R)-3-acetoxybutyronitrile (1) and inhibited that of (S)-1.
Oxidation of trans-1,2-Cyclohexanediaminetetraacetatocobaltate(II) by Peroxodiphosphate Catalyzed by Ag(I) in Acetate Buffers. A Kinetic Study
Authors: Sivaswaroop Pathaneni , Anandkumar Kondapi , Rao Panuganti V K 
Published: July 2006

Abstract
The kinetics of oxidation of trans-1,2-cyclohexanediaminetetraacetatocobaltate(II) by peroxodiphosphate (PDP) in acetate buffers was studied in the presence of Ag(I). For the first time, this study gives a clear evidence for the involvement of Ag(I)/Ag(II) cycle in the Ag(I)-catalyzed PDP oxidation reactions in acetate buffers. A plausible mechanism consistent with the observed kinetic features is proposed.
Cumulene Hosts: Synthesis and Inclusion Property of Tetraaryl-Substituted Butatrienes. X-Ray Crystal Structures of an Unsolvated Host and Its 1 : 2 Inclusion Compounds with o- and p-Xylene
Authors: Weber Edwin , Seichter Wilhelm , Wang Ru-Ji , Mak Thomas C W 
Published: July 2006

Abstract
A series of tetraaryl-substituted cumulenes were synthesized and characterized by elemental analysis, 1H NMR, and MS spectra. Their inclusion capabilities for a variety of organic solvents were examined. It was found that substitution on the phenyl groups connected to both ends of these cumulenes critically influences their inclusion behavior since the substituents dictate the size and shape of lattice space for accommodation of the guest molecules. The crystal structures of an unsolvated butatriene and its 1 : 2 inclusion compounds with p-xylene and o-xylene were determined by X-ray crystallography. The structural analysis showed that the guest molecules do not simply fit into the free space of the host lattice, but their presence rearranges the packing mode of the host molecules in the inclusion compounds.
Chemical Shift Standards in High-Resolution Solid-State NMR (2) 15N Nuclei
Authors: Hayashi Shigenobu , Hayamizu Kikuko 
Published: July 2006

Abstract
15N NMR spectra of the shift standard compound, pure nitromethane, have been measured with high resolution by spinning the liquid sample at the magic angle. Using the precise resonance position of nitromethane, the chemical shifts of the solid second-standard materials such as ammonium salts and glycine have been measured with great precision.
Synthesis and Molecular Structure of Europium(III) Complex with 2,6-Diacetylpyridine Bis(2-pyridylhydrazone)
Authors: Sakamoto Masatomi , Matsumoto Naohide , Okawa Hisashi 
Published: July 2006

Abstract
The title complex, [Eu(NO3)2(L)(CH3OH)]NO3, has been synthesized and its molecular structure has been determined by a single crystal X-ray analysis, where L denotes 2,6-diacetylpyridine bis(2-pyridylhydrazone). The complex has a ten-coordinate structure with quinquedentate L, two bidentate NO3− ions, and monodentate CH3OH.
The Correct Structure of Cyclic Adducts of (Diphenylmethylene)oxophenylphosphorane with Aromatic Aldehydes
Authors: Kawashima Takayuki , Inamoto Naoki 
Published: July 2006

Abstract
The title cyclic adducts have been reported to be 4-aryl-2,3,3-triphenyl-1,2-oxaphosphetane 2-oxides. However, these compounds are concluded not to be the 1,2-oxaphosphetanes, but 1-aryl-3,4-diphenyl-3,4-dihydro-1H-2,3-benzoxaphosphorin 3-oxides from our detailed NMR studies and the investigation of the chemical behavior of the adduct of benzaldehyde.
Effects of Pretreatment of Yubari Coal by Solvent-Extraction on the Reductive Alkylation with Molten Potassium and Iodoethane
Authors: Miyake Mikio , Tamada Kazushi , Minami Hiroo , Nomura Masakatsu 
Published: July 2006

Abstract
Effects of pretreatments of Yubari coal by solvent-extraction on the reductive alkylation with molten potassium and iodoethane have been investigated by comparing the reactions with and without ultrasonic irradiation. Important roles of electron-transfer agents and secondary bonds between coal macromolecules on the anionization were elucidated.
Depth Profiling of Ultra Thin Film Using Laser Induced Fluorescence Spectroscopy under Normal Incidence Conditions Based on the Reciprocal Principle
Authors: Wu Xing-Zheng , Kitamori Takehiko , Teramae Norio , Sawada Tsuguo 
Published: July 2006

Abstract
Depth profiling for thin film sample using laser induced fluorescence spectroscopy under normal incidence conditions, based on the principle of reciprocity, was studied. A laminated Langmuir–Blodgett model film sample (187 nm in thickness) with a concentration depth profile which varies as a stair-like function with 20.8 nm steps was prepared. Using this model film sample, observation angle dependence of fluorescence intensity was compared with theoretical results based on the principle of reciprocity, and it was shown that the principle held for the thin film sample having a continuous concentration depth profile. Secondly, these data were used to reconstruct the concentration depth profile by the least square method. The quantitative concentration depth profiling results obtained for the model film sample were satisfactory. This method can be used for film samples thinner than the wavelength of the excitation light and its spatial resolution in the depth direction is estimated to be in the order of a nanometer.
X-Ray Crystal Structures of Ti(IV)-4,4′-Methylenebis(antipyrine) Complexes, [Ti(dam)3](ClO4)4. Formation of Eight-Membered Chelate Rings and Aromatic Ring Stacking Responsible for Characteristic Coloration
Authors: Yuchi Akio , Shiro Motoo , Wada Hiroko , Nakagawa Genkichi 
Published: July 2006

Abstract
X-Ray crystallographic studies have been made for two Ti(IV) complexes with 4,4′-methylenebis(antipyrine) (so-called diantipyrylmethane, abbreviated to dam) used for spectrophotometry of Ti(IV). The crystal data and final R values are: [Ti(dam)3](ClO4)4 (1), triclinic, P\bar1, a=15.099(2), b=22.308(2), c=14.015(2) Å, α=100.00(1), β=116.68(1), γ=87.16(1)°, V=4151(1) Å3, Z=2, R=0.124 for 8060 reflections; [Ti(dam)3](ClO4)4·H2O (2), monoclinic, P21⁄c, a=14.075(3), b=29.127(7), c=21.386(6) Å, β=122.42(1)°, V=7401(3) Å3, Z=4, R=0.105 for 6685 reflections. The reagent dam acts as a bidentate ligand to form eight-membered chelate rings. Between a pyrazolone moiety of one ligand and a phenyl ring of another prevails aromatic ring stacking, which gives extra stability to these complexes and is responsible for the characteristic charge transfer band around 385 nm.
Kinetic Studies on the Cobalt(II) Naphthenate Catalyzed Decomposition of “Cumene Hydroperoxide” in Benzene
Authors: Sawada Hideo , Ishigaki Hideyo , Kato Mitsukuni , Nakayama Masaharu 
Published: July 2006

Abstract
The cobalt(II) naphthenate[Co(Nap)2] catalyzed decomposition of cumene hydroperoxide(CHP) gave a mixture of α-cumyl alcohol, acetophenone and di-α-cumyl peroxide in benzene at 25°C. All experimentally observed time courses of disappearing CHP and an increasing of three products compared well with theoretical values.
Structure and Optical Properties of Thermochromic Schiff Bases. Charge Transfer Interaction and Proton Transfer in the N-Tetrachlorosalicylideneaniline and N-Tetrachlorosalicylidene-1-pyrenylamine Crystals
Authors: Inabe Tamotsu , Gautier-Luneau Isabelle , Hoshino Naomi , Okaniwa Kaoru , Okamoto Hiroshi , Mitani Tadaoki , Nagashima Umpei , Maruyama Yusei 
Published: July 2006

Abstract
Two kinds of N-salicylideneaniline derivatives, N-tetrachlorosalicylideneaniline (CL4SA) and N-tetrachlorosalicylidene-1-pyrenylamine (CL4SPY), have been prepared and subjected to structural and optical studies in the crystalline state. A thermochromic-type behavior of the former crystal has been observed as a shift of the absorption edge, while that of the latter crystal is much less pronounced. Fairly short O–H···N hydrogen bonds have been found in both compounds through crystallographic studies, which may be mainly due to a steric effect of chlorine substituents. The difference in the proton transfer behavior of CL4SA and CL4SPY should presumably be caused by an intermolecular charge-transfer interaction in the latter crystal.
NAD(P)H-NAD(P)+ Models. 73. Structure-Stereochemistry Relationship in the Reaction of NAD Analog
Authors: Ohno Atsuyoshi , Mikata Yuji , Goto Mutsuo , Kashiwagi Takeshi , Tanaka Takanori , Sawada Masami 
Published: July 2006

Abstract
Four different NAD(P)H analogs have been oxidized by various substituted and unsubstituted 1,4-benzoquinones in the presence or absence of magnesium ion. The stereospecificity of the reaction depends not only on the reactivity of quinone but also on that of the analogs as well as on the presence or absence of magnesium ion. The results are discussed from the viewpoint of reaction mechanism for the transfer of a (net) hydride ion.
The 2.0 Å Crystal Structure of Cyanide Metmyoglobin Reconstituted with 5,10,15,20-Tetrapropylhemin
Authors: Hata Tadashi , Hata Yasuo , Sato Takao , Tanaka Nobuo , Neya Saburo , Funasaki Noriaki , Katsube Yukiteru 
Published: July 2006

Abstract
Sperm whale metmyoglobin reconstituted with 5,10,15,20-tetrapropylhemin was crystallized in the space group P212121, which was different from the space group P21 of the native. The crystal structure of the reconstituted metmyoglobin was determined by the molecular replacement method. The atomic coordinates were refined to R=0.209 at 2.0 Å resolution. The overall structure is essentially the same as that of the native. The pronounced structural change is observed in the side-chain orientation of Arg 45 moving to the surface of the molecule. This conformational change may reflect a side-chain fluctuation that allows the small ligands to approach the heme pocket from the outside of the protein. The porphyrin ring does not rotate freely about the Fe–Nε (His 93) bond in the crystalline state, although temperature-dependent NMR spectra suggest its free rotation in solution.
Rearrangement of 4-Perfluoroalkyl Quinols
Authors: Uno Hidemitsu , Shiraishi Yasukazu , Matsushima Yuji , Yayama Ayumi , Suzuki Hitomi 
Published: July 2006

Abstract
Treatment of 4-perfluoroalkyl-4-hydroxy-2,5-hexadien-1-one (4-perfluoroalkyl-4-quinol), prepared from the reaction of 1,4-benzoquinone with perfluoroalkyllithium, with acetic anhydride–sulfuric acid gave a mixture of 2,4-diacetoxy-1-perfluoroalkylbenzene and 1,2-diacetoxy-4-perfluoroalkylbenzene in a comparable ratio. When 4-perfluoroalkyl-4-quinols bearing a methyl group ortho to the perfluoroalkyl group were subjected to the rearrangement, acetoxymethyl compounds were obtained in addition to diacetoxybenzene derivatives. Only 1,3-migration was observed in the cases of 2,4-di-t-butyl-4-perfluorooctyl-4-quinol and 4-hydroxy-4-perfluoroalkyl-1(4H)-naphthalenone, while the reaction of 2,6-dimethyl and 2-methoxy derivatives gave only 1,2-shift products. Reaction routes to the apparent 1,2- and 1,3-acetoxyl migration products are discussed.
Reactions of Methoxynaphthalenes with Active Methylene Compounds in the Presence of Manganese(III) Acetate
Authors: Tsunoda Katsunori , Yamane Mitsuyoshi , Nishino Hiroshi , Kurosawa Kazu 
Published: July 2006

Abstract
The reaction of methoxynaphthalenes with malonamide in the presence of magnanese(III) acetate gives 2-acetoxy-2-(1-naphthyl)propanediamides and 2-hydroxy-2-(1-naphthyl)propanediamides. It was found that the propanediamidation reaction did occur when naphthalenes have electron-donating substituents, such as a methoxyl group. The reactions of methoxynaphthalenes with ethyl 3-oxobutanoate, 2-cyanoacetamide, and malononitrile in the presence of manganese(III) acetate also yielded the corresponding substituted naphthalenes, ethyl 2-(acetoxymethyl)naphtho[2,1-b]furan-1-carboxylates, and/or a 4-methylene-1(4H)-naph-thalenone. The reaction mechanisms are discussed.
Synthesis of 5,6-Dideoxy-5-phenylphosphinyl-l-galactopyranoses. The P-in-Ring Sugar Analogs of l-Fucose
Authors: Hanaya Tadashi , Yamamoto Hiroshi , Ohmae Takeshi , Kawamoto Heizan , Armour Margaret-Ann , Hogg Alan M , Yamamoto Hiroshi 
Published: July 2006

Abstract
1,2-O-Isopropylidene-3-O-methyl-6-O-tosyl-β-d-arabino-hexofuranos-5-ulose (9a) and its 3-O-benzyl congener (9b) were prepared from 1,2:5,6-di-O-isopropylidene-β-d-altrofuranose in 4 steps. Addition of methyl phenylphosphinate to 9a and 9b in the presence of DBU, followed by reduction with Raney Ni, afforded (5R and 5S)-5,6-dideoxy-1,2-O-isopropylidene-5-[(methoxy)phenylphosphinyl]-3-O-methyl-β-d-arabino-hexofuranose(11a) and 3-O-benzyl congener (11b), respectively. The latter compound (11b) was debenzylated to 3-O-unsubstituted hexofuranose 11d. By reduction with sodium dihydrobis(2-methoxyethoxy)aluminate, followed by acid hydrolysis, these key intermediates 11a, 11b, and 11d provided the title l-fucoses 13 (together with a minor proportion of d-altropyranoses 14) having as phenylphosphinylidene group in place of the ring oxygen. Compounds 13 and 14 were converted into per-O-acetyl derivatives for structural and conformational analysis by spectroscopy.