Process and intermediates useful to produce vitamin D analogs
申请人:Hoffmann-La Roche Inc.
公开号:US06353123B1
公开(公告)日:2002-03-05
A stereospecific method for accomplishing the below reaction:
results in the compound of formula 2 having the same stereochemistry at both carbon 1 and carbon 3 as that in the compound of formula 1. Thus, if carbon 3 is in the R-configuration in the compound of formula 1, then carbon 3 will be in the R-configuration in the compound of resulting formula 2. In the above process, R1 is C1-C6 alkyl that can be straight-chain or branched. The process functions using a fluorinated alcohol having a pKa less than about 9, in the presence of a palladium catalyst. The compounds of formula 1, as well as novel intermediates in this process, are useful in manufacturing vitamin D analogs.
Efficient Synthesis of 1α-Fluoro A-Ring Phosphine Oxide, a Useful Building Block for Vitamin D Analogues, from (<i>S</i>)<i>-</i>Carvone via a Highly Selective Palladium-Catalyzed Isomerization of Dieneoxide to Dieneol
作者:Marek M. Kabat、Lisa M. Garofalo、Andrzej R. Daniewski、Stanley D. Hutchings、Wen Liu、Masami Okabe、Roumen Radinov、Yuefen Zhou
DOI:10.1021/jo015788y
日期:2001.9.1
block for fluorinated vitamin D analogues, was synthesized from (S)-carvone in 13 synthetic steps, and only five isolations, in 22% overall yield. In the key synthetic step, a highlyselective palladium-catalyzed isomerization of dieneoxide 18 to dieneol 20 was achieved using an appropriately selected fluorinated alcohol as a catalytic proton source.