One-Carbon Bridge Stereocontrol in Robinson Annulations Leading to Bicyclo[3.3.1]nonanes
作者:Dong Wang、William E. Crowe
DOI:10.1021/ol1000878
日期:2010.3.19
The one-carbon bridge stereochemistry of bicyclo[3.3.1]nonane products formed in the Robinson annulation reactions of 2-substituted cyclohex-2-enones was investigated. In contrast to previous reports, it was found that the major diastereomer formed places the one-carbon bridge substituent anti to the β-keto ester/amide unit introduced in the Robinson annulation. This stereoselectivity appears to be
Cyclopentannulation of Conjugated Enones Using a Vinyldiazomethane-Based Reagent
作者:Matthew Del Bel、Alexander Rovira、Carlos A. Guerrero
DOI:10.1021/ja4054866
日期:2013.8.21
(1) as a bifunctional reagent. The enol silane and stabilized diazoalkane functionalities are exploited independently in sequential Mukaiyama-Michael and diastereoselective α,α'-diketone coupling. Di-, tri-, and tetrasubstituted enones are amenable to annulation under this protocol. Overall, this chemistry is an effective surrogate for a substituted "acetone 1,3-dipole".