ABSTRACT
Cesium fluoride catalyzed direct cyanomethylation of various isatins by using trimethylsilyl acetonitrile (TMSAN) as a nucleophile has been developed. The reaction has been explored for a number of isatins, with various substitutions on its aromatic ring. Further, the versatility of the reaction is demonstrated by converting the direct aldol adducts to the corresponding intermediates of natural products and medicinally important compounds.
ABSTRACT
The asymmetric vinylogous Michael reaction of cyclohexenone/medium and large cyclic enones with 2-silyloxyfuran is still a synthetic challenge. In this report, we have explored 1,4-conjugate addition of an enantioselective chiral, primary diamine catalyzed, 2-silyloxy furan to various cyclic enones and ß-substituted cyclic enones. The reaction provided syn-Michael adducts (cycloalkane connected γ-butenolide) with good yields, diastereo and enantioselectivities. Furthermore, the synthetic potential of these syn-Michael adducts is demonstrated by 1,4-addition of nucleophiles on the butenolide substructure.
