T. Murata, Yumiko Yanagisawa, M. Aoyama
Dec 11, 1998
Citations
0
Influential Citations
6
Citations
Journal
Tetrahedron-asymmetry
Abstract
Abstract The reaction of (Z)-3-deoxy-3-C-[(hydroxymethyl)methylene]-1,2:5,6-di-O-isopropylidene-α-D-ribo-hexo-furanose, prepared from D-glucose, with 1,1-dimethoxycyclohexane in the presence of propanoic acid at 135°C, then at 200°C, provided two Claisen rearrangement products, namely (2R,3R,4S,5S)-2,3-(isopropylidene)dioxy-5-[(1R)-1,2-(isopropylidene)dioxyethyl]-4-[(1S)- and (1R)-2-oxocyclohexyl]-4-vinyltetrahydrofuran in a ratio of 3.3:1. L-Selectride® reduction of the major product gave the corresponding (S)-cyclohexanol exclusively. In contrast, the Claisen rearrangement of the aforementioned allylic alcohol with 3,3-dimethoxycyclohexene proceeded with complete stereoselectivity to provide the corresponding 4-[(1S)-2-oxocyclohex-3-enyl]-4-vinyltetrahydrofuran exclusively. The 1,4-conjugate additions to the thus formed cyclohexenone derivative with dimethyl and divinylcuprates proceeded with complete π-facial selection to provide the 3-methylated and 3-vinylated cyclohexanone derivatives, both in high yields.