The Chemistry of 2H-3,1-Benzoxazine-2,4(1H)-dione (Isatoic Anhydride). 201. Synthesis and Wittig Reactions of Dimethyl (4-Oxo-1,4-dihydro-Quinolin-2-yl)methanephosphonates
Remarkable Phosphine-Effect on the Intramolecular Aldol Reactions of Unsaturated 1,5-Diketones: Highly Regioselective Synthesis of Cross-Conjugated Dienones
作者:Reema K. Thalji、William R. Roush
DOI:10.1021/ja054085l
日期:2005.12.1
We report a phosphine-mediated intramolecular aldolcyclization of unsaturated diketones that proceeds with extremely high levels of regioselectivity for the cross-conjugated bicyclic dienone products. The sense of regioselectivity observed in this reaction is complementary to that obtained using traditional aldol conditions. Experimental evidence that supports the involvement of a phosphine Michael
Synthesis of juvabione in short steps in a high overall yield has been achieved via the chemoselective reduction with Hantzsch ester (HEH) in the presence of silica gel as a key step.