convenient procedure for the synthesis of homoallylic alcohols from carbonyl compounds and allylboranes is described. Allyl-, 2-methylallyl-, crotyl- and 3,3-dimethylallyl(dialkyl)boranes, as well as diallyl(alkyl)boranes and derivatives of 3-allyl- and 3-metallyl-3-borabicyclo[3.3.1]non-6-ene are effective reagents for allylation of carbonyl compounds (aldehydes, ketones, esters, carboxylic acids and others)
An isobutyl group placed equatorially in the 2-position of a 1-equatorially substituted cyclohexane adopts a preferred conformation (cf. 5). This also holds when it is placed in the 2-position on a 3-equatorially substituted tetrahydropyran (cf. 6). The same conformational preference is found for 2-methoxypropyl residues in the 2-position of 3-substituted tetrahydropyrans (cf. 8 and 10). The latter compounds chelate lithium cations as analogues of 1,2-dimethoxyethane. Through this complexation, it is possible to effect a change in the side chain conformation.
MIXAJLOV B. M.; BUBNOV YU. N.; TSYBAN A. V., IZV. AN CCCP CEP. XIM., 1978, HO 9, 1892-1897
作者:MIXAJLOV B. M.、 BUBNOV YU. N.、 TSYBAN A. V.
DOI:——
日期:——
MIKHAILOV B. M.; BUBNOV Y. N.; TSYBAN A. V.; GRIGORYAN M. S., J. ORGANOMETAL. CHEM., 1978, 154, NO 2, 131-145
作者:MIKHAILOV B. M.、 BUBNOV Y. N.、 TSYBAN A. V.、 GRIGORYAN M. S.