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Pyridine-borane

O-linked polymer-bound Af-substituted hydroxylamines are prepared by reduction of resin-bound oximes with borane-pyridine complex in the presence of dichloroacetic acid (Scheme 94). Other reducing systems commonly used for imine or oxime reduction are ineffective, including borane-pyridine in the presence of acetic acid. Subsequently, the A-substituted products are acylated and cleaved from the resin to afford Af-substituted hydroxamic acids 220. ... [Pg.214]

Thiophenes can also be desulfurized to alkenes (RCH2CH=CHCH2R from 23) with a nickel boride catalyst prepared from nickel(II) chloride and NaBH in methanol.419 It is possible to reduce just one SR group of a dithioacetal by treatment with borane-pyridine... [Pg.728]

A similar chiral environment is given by inclusion to cyclodextrins (CDs), cyclic oligosaccharides (3). The outside of the host molecule is hydrophilic and the inside hydrophobic. The diameters of the cavities are approximately 6 (a), 7-8 (j3), and 9-10 A (7), respectively. Reduction of some prochiral ketone-j3-CD complexes with sodium boro-hydride in water gives the alcoholic products in modest ee (Scheme 2) (4). On the other hand, uncomplexed ketones are reduced with a crystalline CD complex of borane-pyridine complex dispersed in water to form the secondary alcohols in up to 90% ee, but in moderate chemical yields. Fair to excellent enantioselection has been achieved in gaseous hydrohalogenation or halogenation of a- or /3-CD complexes of crotonic or methacrylic acid. These reactions may seem attractive but currently require the use of stoichiometric amounts of the host CD molecules. [Pg.377]

Benzo[b]thiophene Acetaldehyde Borane pyridine complex Trimethylsilyl isocyanate... [Pg.3540]

Reductive amination of carbonyl compounds. Sodium cyanoborohydride has been the reductant of choice for this reaction, even though it is highly toxic (4, 448-449). Borane-pyridine is recommended as a nontoxic substitute. The reactions are conducted in acetic acid, in which this borane is fairly stable, and a co-solvent such as CH2CI2 or THE... [Pg.65]

REDUCTION, REAGENTS Bis(N-methylpi-perazinyl)aluminum hydride. Borane-Di-methyl sulfide. Borane-Tetrahydrofurane. Borane-Pyridine. n-Butyllithium-Diisobu-tylaluminum hydride. Calcium-Amines. Diisobutylaluminum hydride. 8-Hydroxy-quinolinedihydroboronite. Lithium aluminum hydride. Lithium 9-boratabicy-clo[3.3.1]nonane. Lithium n-butyldiisopro-pylaluminum hydride. Lithium tri-j c-butylborohydride. Lithium triethylborohy-dride. Monochloroalane. Nickel boride. 2-Phenylbenzothiazoline. Potassium 9-(2,3-dimethyl-2-butoxy)-9-boratabicy-clo[3.3.1]nonane. Raney nickel. Sodium bis(2-methoxyethoxy)aluminum hydride. Sodium borohydride. Sodium borohy-dride-Nickel chloride. Sodium borohy-dride-Praeseodymium chloride. So-dium(dimethylamino)borohydride. Sodium hydrogen telluride. Thexyl chloroborane-Dimethyl sulfide. Tri-n-butylphosphine-Diphenyl disulfide. Tri-n-butyltin hydride. Zinc-l,2-Dibromoethane. Zinc borohydride. [Pg.583]

REDUCTION, REAGENTS Bis(triphenyl-phosphine)copper tetrahydroborate. Borane-Pyridine. Calcium-Methylamine/ ethylenediaminc. Chlorobis(cyclopenta-dienyl)tetrahydroboratozirconium(IV). Chromium(II)-Amine complexes. Copper(0)-lsonitrile complexes. 2,2-Dihydroxy-l, 1-binaphthyl-Lithium aluminum hydride. Di-iododimethylsilane. Diisobutyl-aluminum 2,6-di-/-butylphenoxide. Diisobutyl aluminum hydride. Dimethyl sulfide-Trifluoroacetic anhydride. Disodium tetracarbonylferrate. Lithium-Ammonia. Lithium-Ethylenediamine. Lithium bronze. Lithium aluminum hydride. Lithium triethylborohydride. Potassium-Graphite. 1,3-Propanedithiol. Pyridine-Sulfur trioxide complex. [Pg.270]

Reductions in tiifiuoroaeetie acid. Borane-pyridine in refluxing benzene is a rather weak reducing agent. When used in trifiuoroacetic acid it has much stron r reducing properties. It has been used to effect a number of useful reductions, such as those shown. ... [Pg.336]

Boran Pyridin-Dimethyl-hydrose-leno- XIII/3b, 638... [Pg.399]

The BH3 adduct of 2-aminopyridine seems to be very stable to internal hydroboration and polymerisation compared to borane pyridine. We attribute the extra stability to hydride-proton interactions these together with those of fluorine-proton were reported for other amine borane compounds16 (Figure 5). The MM models for the two boron complexes shown in Figure 6, present atomic distances... [Pg.423]

See other pages where Pyridine-borane is mentioned: [Pg.63]    [Pg.403]    [Pg.532]    [Pg.941]    [Pg.378]    [Pg.71]    [Pg.116]    [Pg.78]    [Pg.137]    [Pg.59]    [Pg.115]    [Pg.371]    [Pg.115]    [Pg.371]    [Pg.246]    [Pg.314]    [Pg.377]    [Pg.72]    [Pg.2056]    [Pg.2264]    [Pg.64]    [Pg.3541]    [Pg.1052]    [Pg.333]    [Pg.108]    [Pg.65]    [Pg.663]    [Pg.65]    [Pg.506]    [Pg.901]    [Pg.929]    [Pg.1172]    [Pg.43]   
See also in sourсe #XX -- [ Pg.69 ]

See also in sourсe #XX -- [ Pg.65 ]

See also in sourсe #XX -- [ Pg.65 ]

See also in sourсe #XX -- [ Pg.59 ]



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Borane-pyridine adducts

Pyridine borane esters

Pyridine complex with borane

Pyridine-borane complex

Pyridines reactions with boranes

Reduction pyridine.Borane

Reductive amination pyridine borane

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