Cycloaddition of Cyclohexa-2,4-dienones, Ring-Closing Metathesis, and Photochemical Reactions: A Common Stereoselective Approach to Duprezianane, Polyquinane and Sterpurane Frameworks
作者:Vishwakarma Singh、G. D. Praveena、Kapil Karki、Shaikh M. Mobin
DOI:10.1021/jo062416m
日期:2007.3.1
appropriately appended cyclohexa-2,4-dienones with acyclic dienes gave bridged bicyclic octanes suitably disposed with olefinic chains, which upon ring-closing metathesis led to functionalized tricyclo[5.2.2.01,5]undecanes related to dupreziananes. Photochemical sigmatropic 1,2- and 1,3-acyl shifts in tricyclo[5.2.2.01,5] undecanes upon triplet and singlet excitation provided stereoselective routes to sterpurane
Molecular complexity from aromatics. Cycloaddition of spiroepoxycyclohexa-2,4-dienones and intramolecular Diels–Alder reaction: a stereoselective entry into tetracyclic core of atisane diterpenoids
作者:Vishwakarma Singh、Pravin Bhalerao、Bharat Chandra Sahu、Shaikh M. Mobin
DOI:10.1016/j.tet.2012.10.051
日期:2013.1
cycloaddition with ethyl acrylate furnished bridgedbicyclo[2.2.2]octanes disposed with appropriate functionality. Regioselective manipulation of functional groups led to highly embellished bicyclic systems endowed with appendages containing diene and dienophilic moieties that upon inverse electron demand intramolecular cycloaddition provide the tetracyclic framework of atisanes in stereoselective fashion
Diels−Alder Cycloaddition and Ring-Closing Metathesis: A Versatile, Stereoselective, and General Route to Embellished Bridged Bicyclic Systems, Carbocyclic Framework of Secoatisanes, and Homologues
作者:Vishwakarma Singh、Pramod K. Sahu、Bharat C. Sahu、Shaikh M. Mobin
DOI:10.1021/jo901279g
日期:2009.8.21
A general and stereoselective methodology for the synthesis of bridged bicyclic octenones having various types of alkenyl chains and a tricyclic framework of secoatisanes and higher analogues is reported. In situ generation and cycloaddition of 2-allyl-6,6-spiroepoxycyclohexadienones with ethyl acrylate gave bicyclo[2.2.2]octaneshaving an allyl group at the bridgehead and other chemically distinguishable