Enantioselective rhodium-mediated synthesis of (-)-PGE2 methyl ester
作者:Douglass F. Taber、R. Scott Hoerrner
DOI:10.1021/jo00028a012
日期:1992.1
Intramolecular Rh(II) carboxylate catalyzed cyclization of an alpha-diazo beta-methylene ketone to form a fused cyclopropane is shown to compete efficiently with beta-hydride elimination, so long as a catalyst derived from an electron-donating carboxylate is used. Cyclization of diazoketone 3 gives 2, which on opening with thiophenol followed by oxidative rearrangement gives PGE2 methyl ester 1. Prostaglandins having the 8-beta configuration, recently identified as being physiologically important, can also be prepared using this approach.
JOHNSON, CARL R.;PENNING, THOMAS D., J. AMER. CHEM. SOC., 110,(1988) N 14, C. 4726-4735
作者:JOHNSON, CARL R.、PENNING, THOMAS D.
DOI:——
日期:——
Diisobutylaluminum 2,6-Di-<i>t</i>-butyl-4-methylphenoxide. Novel Stereoselective Reducing Agent for Prostaglandin Synthesis
reducing agents suitable for prostaglandinsynthesis, diisobutylaluminum 2,6-di-t-butyl-4-methylphenoxide (1) is found to be among the best. Reduction of the C-15 ketone with 1 in toluene at −78 °C produced the desired 15S-alcohol in 95% yield with 92% stereoselectivity. The present procedure is suitable for the synthesis of prostaglandin derivatives and related polyfunctional natural products as shown in