Lithium tri-j-butylborohydride

The NMR spectrum of the cis-fused quinolizidol (64a) and its derivatives showed the presence of an equilibrium mixture of conformers where the form with an axial OH and equatorial phenyl group was only a minor component. The signal of H-l in 64b-d appears at <5 4.0-4.1 ppm as a triplet with a coupling constant of 4-5 Hz and W1/4 of 13-14 Hz. H-3 was in part unresolved from H-l in 64a,e and in 64c,d was a broad multiplet (a triplet of triplets with J 8-9 and 4.5 Hz) with W1/4 equal to 25-28 Hz. These couplings of H-l and H-3 favor that conformation with an axial phenyl and an equatorial hydroxyl. Compound 64a was synthesized by reduction of cis-fused quinolizidone (65b) with NaBH4 to yield mixture of 64a and its epimer in 1.3 1 ratio or with lithium tri-sec-butylborohydride, where 65% conversion to axial alcohol was observed. 

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. 

Reduction of a, -unsaturated nitroalkenes J These nitroalkenes are reduced by lithium tri-.vt c-butylborohydride or by lithium triethylborohydride to lithium nitronates, which are hydrolyzed by dilute acid or by silica, - cl to nitroalkanes (equation I). 

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