Aluminum, tris reduction

Reduction of Cholest-5-en-3-one with Lithium Aluminum Tri-t-butoxy Deuteride. 

In further modifications of these norprogestins, reaction of norethindrone with acetic anhydride in the presence of p-toluene-sulfonic acid, followed by hydrolysis of the first-formed enol acetate, affords norethindrone acetate (41). This in turn affords, on reaction with excess cyclopentanol in the presence of phosphorus pentoxide, the 3-cyclopentyl enol ether (42) the progestational component of Riglovic . Reduction of norethindrone affords the 3,17-diol. The 33-hydroxy compound is the desired product since reactions at 3 do not show nearly the stereoselectivity of those at 17 by virtue of the relative lack of stereo-directing proximate substituents, the formation of the desired isomer is engendered by use of a bulky reducing agent, lithium aluminum-tri-t-butoxide. Acetylation of the 33,173-diol iffords ethynodiol diacetate, one of the most potent oral proves tins (44). ... 

The 8-methyl-8,14-cycloberbine 364, derived from the protoberberine 324 via the betaine 363, was reduced with sodium borohydride or lithium aluminum tri-tert-butoxyhydride to give a diastereoisomeric mixture of cis-and trans-alcohols (7.8 1 or 1 7.8, respectively) (Scheme 64).t)n exposure to formaldehyde the mixture underwent N-hydroxymethylation and subsequent intramolecular substitution on the aziridine ring to give the oxazolidine 365. Removal of the hydroxyl group in 365 was accomplished by chlorination followed by hydrogenolysis with tributyltin hydride. Reductive opening of the oxazolidine 366 with sodium cyanoborohydride afforded ( )-raddeanamine (360), which has already been converted to ochotensimine (282) by dehydration. 

Lithium aluminum tri-/-butoxyhydride in reduction of 3/3-acetoxy-5-pregnene-20-one, 45, 58... 

As to the preparation of MAM, the exact same sequence was used, except for the employment of n-amyl bromide. The benzaldehyde crystallized from methanol with amp of79-80 °C, and formed amalononitrile derivative which was bright yellow and melted at 103-104 °C. The nitrostyrene, when pure, melted at 57-58.5 °C but proved very difficult to separate from the aldehyde. The final product, 4-(n)-amyloxy-2,5-dimethoxyamphetamine hydrochloride (MAM) was obtained by lithium aluminum hydride reduction in ether and melted at 125-127 °C. It was assayed at up to 16 milligrams, at which level there was noted a heaviness in the chest and head at the 2-hour point, but no cardiovascular disturbance and no mydriasis. This was called an inactive level, and no higher one has yet been tried. 

Lithium aluminum tri-l-butoxyhydride in reduction of 30-acetoxy-S-pregnene-20-one, 46, 58 Lithium amalgam, reaction with 3,4-dichloro-1,2,3,4-tetramethylcy-clobutene, 46, 36... 

Pregnenolone acetate, reduction with lithium aluminum tri-l-butoxy-hydride, 46, 58... 

The sodium borohydride reduction of l-[j8-(3-indolyl)ethyl]-3-hydroxymethylpyridinium bromide (100, R = H) affords a 73% yield-of the 3-piperideine (101), but with the use of lithium aluminum hydride a 50% yield of the diene (102) is obtained. The lithium tri-f-butoxy aluminum hydride reduction of (100) leads to a mixture... 

Acetoxy-5-pregnene-20-one, reduction by lithium aluminum tri-t-butoxyhydride, 46, 57... 

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