Abstract
An efficient synthesis of the title compound (5) from Thiele's ester (1b) is described. Thus, LiAlH4 promoted reduction of dimethyl pentacyclo[5.4.0.02,5.03,904,8]decane-2,5-dicarboxylate (2) produced the corresponding diol, 3, in 80% yield. Reaction of 3 with NaH-MsCl followed by LiAlH4 promoted reduction of the crude product thereby obtained resulted in the formation of the title compound (5, 12% yield) accompanied by a cage-annulated oxa[3.3.2]propellane, 6, which proved to be the major reaction product (22% yield). Reaction of 3 with Et3N-MsCl afforded the corresponding dimesylate, 4, in essentially quantitative yield). Subsequent LiAlH4 promoted reduction of 4 gave 5 in 66% yield.
ACKNOWLEDGMENT
We thank the Office of Naval Research (Grant N00014-98-1-0478) and the Robert A. Welch Foundation (Grant B-963) for financial support of this study. In addition, we thank Professor Jennifer S. Brodbelt (Department of Chemistry, University of Texas at Austin) for having kindly obtained highresolution chemical ionization mass spectral data reported herein.