Carbinols s. a. Alcohols

S)-4-Anilino-3-methylamino-l-butanol (22a) and (S)-4-(2,6-xylidino)-3-methylamino-l-butanol (22b), tridentate chiral auxiliaries, are easily derived from (S)-aspartic acid. A complex (56a) prepared from equimolar amounts of LAH and (22a) in THF reduces aromatic ketones to (S)-carbinols in 51-88% ee. This complex is also effective in reducing several enones to (S)-allylic alcohols (Scheme 12), whereas the complex (56b) affords the () )-enantiomers. Particularly noteworthy is the virtually complete en-antiofacial differentiation of cyclohexenone giving (S)-2-cyclohexenol. ... 

Itsuno s amino alcohol (70), prepared from L-valine, is an extremely efficient auxiliary for enantioselective reduction of aryl alkyl ketones using BH3. The corresponding alcohols are obtained in up to 100% ee using BH3 and 0.5 equiv. of (70) in THF at 30 °C. Reduction of dialkyl ketones affords (R)-carbinols in 55-73% ee. Halomethyl t-butyl ketones are also converted to the corresponding (5)-carbinols in high optical purity (Scheme 15). Immobilized amino alcohol (70) permits reduction in a continuous flow system. 1-Phenylpentanol of 90% ee was prepared by this catalytic process in almost 1000% chemical yield based on the quantity of chiral auxiliary used. ... 

Methylamino-4-acetoxyacetophenone hydrochloride in water hydrogenated with 20 % -Pd-on-carbon until the theoretical quantity of Hj is absorbed after 6 hrs during which the mixture is heated 3 times to ca. 80° —methylaminomethyl-(4-acetoxyphenyl)-carbinol hydrochloride. Y 90%. (F. e. and optimum reaction conditions s. H. Bretschneider, M. 77, 385 (1947) s. a. 78, 71 (1948) a-Amino-see. alcohols from a-ketoaldehydes s. 5, 314.)... 

Normal butyl alcohol, propyl carbinol, n-butanol, 1-buianol, CH3CH2CH2CH2OH. B.p. 117 C. Manufactured by reduction of crotonaldehyde (2-buienal) with H2 and a metallic catalyst. Forms esters with acids and is oxidized first to butanal and then to butanoic acid. U.S. production 1978 300 000 tonnes. 

A aoriea of newly-disoovfcicd corisiitueuts, present in irace.s ouly, has also been deacribi-d by fJ. Masson.- These bodies arc as follows msthji-amyl-carbinol, methvi-heptji-carbinol, benzyl alcohol, and di-raethyl-lurfurol,... 

Methyl isobutyl ketone was reduced with (- )-menthol-LAH in ether to give the (+ )-(S)-carbinol (53) in low optical yield. Methyl neopentyl ketone was similarly reduced to the (-I- )-carbinol, although pinacolone was reduced to only racemic alcohol. Maximum stereoselectivity in the reduction of both ketones and alkenynols was obtained with a 2 1 (-)-menthol-LAH reagent. The observed low stereoselectivity was attributed mainly to insufficient interaction of the remote isopropyl substituent on the menthyl group with the substituents on... 

The asymmetric epoxidation of an allylic alcohol in which the carbinol has been replaced by a silanol has been described [144]. As shown in Eq. 6A.10 [144], (3 )-phenylethenyldi-methylsilanol is converted to an epoxysilanol in 50% yield with 85-95% ee. Note that here the longer Si-C bonds appear to overcome the restriction to epoxidation associated with a fully substituted C-l atom in the allylic alcohol series. Fluoride cleavage of the silanol group gives (S)-styrene oxide. 

In the same vein as the cyclic sulfate activation of diols, cyclic sulfamidates have been prepared from 1,2- and 1,3-amino alcohols for the purpose of activating the carbinol toward nucleophilic attack [85-88]. (S)-Prolinol [85], A-benzyl serine t-butyl ester [86], and 2-(2-hy-... 

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