A Highly Regio- and Stereoselective Cascade Annulation of Enals and Benzodi(enone)s Catalyzed by N-Heterocyclic Carbenes
作者:Xinqiang Fang、Kun Jiang、Chong Xing、Lin Hao、Yonggui Robin Chi
DOI:10.1002/anie.201007144
日期:2011.2.18
Three stereogenic centers in a row: The unconventional activation of enal compounds mediated by an N‐heterocyclic carbene (NHC) has generated three consecutive reactive carbon centers that undergo highly regio‐ and stereoselectiveannulations with di(enone)s to generate benzotricyclic products containing multiple stereogenic centers (see scheme).
Stereoselective Rh<sup>I</sup>-Catalyzed Tandem Conjugate Addition of Boronic Acids−Michael Cyclization
作者:Cristina Navarro、Aurelio G. Csákÿ
DOI:10.1021/ol702571c
日期:2008.1.1
The first examples of the stereoselective sequence RhI-catalyzed tandem conjugateaddition of boronic acids to enones-Michael cyclization, is reported. The reaction is carried out in dioxane-H2O at rt, and 1,2,3-trisubstituted indans are obtained in a highly regio- and stereoselective fashion.
Stereoselective Borylcupration/Michael Addition on Symmetrical Dienones
作者:Laxman Devidas Khalse、Prasanta Ghorai
DOI:10.1021/acs.joc.2c02714
日期:2023.7.7
An efficient cascade protocol for the stereoselective synthesis of borylated carbocycles via copper-catalyzed borylative Michael/Michael cyclization is presented. Using this mild approach, up to 24 new boronic ester substituted indanes, cyclohexanes, and cyclopentanes were prepared in good yields with excellent diasteroselectivities and exceptional functional group tolerance. Furthermore, carbacyclic
Enantioselective Copper-Catalyzed Reductive Michael Cyclizations
作者:Claire L. Oswald、Justine A. Peterson、Hon Wai Lam
DOI:10.1021/ol901560r
日期:2009.10.15
In the presence of siloxanes as stoichiometric reductants, chiral copper-bisphosphine complexes catalyze highly enantioselective reductive Michael cyclizations of substrates containing two alpha,beta-unsaturated carbonyl moieties. The diastereochemical outcome of these reactions is dependent upon whether biaryl- or ferrocene-based chiral bisphosphines are employed.