β-Siloxy unsaturated nitriles: stereodivergent cyclizations to cis- and trans-decalins
作者:Fraser F Fleming、Brian C Shook、Tao Jiang、Omar W Steward
DOI:10.1016/s0040-4020(02)01615-0
日期:2003.2
cyclizing instead through a less-congested conformation to trans-decalins. Conjugation of nitrile anions with adjacent sp2 centers prevents pyramidalization, and redirects cyclization through a planar-delocalized anion to cis-decalins. Collectively these cyclizations allow conversion of a single β-siloxynitrile to either cis- or trans-decalins that are ideally suited for elaboration into terpenoid natural
Oxidative DMSO Cyclization Cascade to Bicyclic Hydroxyketonitriles
作者:John Kornfeind、Pravin S. Iyer、Taylor M. Keller、Fraser F. Fleming
DOI:10.1021/acs.joc.2c00364
日期:2022.5.6
Thermolysis of ω-iodoalkyl-β-siloxyalkenenitriles in DMSO triggers an oxidativecyclizationcascade that affords highly oxygenated hydrindanones, decalones, and undecanones. The cyclizationcascade is highly unusual on three counts: the cyclization installs a contiguous array of tertiary–quaternary–tertiary centers, thermolysis equilibrates a quaternary center, and the enolsilyl ether crossed-aldol