摘要 |
<p>A process for producing a compound of the formula: <CHEM> where Ph is phenyl, X<1> and X<2> are both hydrogen or X<1> and X<2> taken together are CH2, R<1> is a protecting group, R<2> is fluorine, hydrogen, or OR<3>, where R<3> is a protecting group, and the squiggly line represents a bond that results in the adjacent double bond being in either the E or Z configuration, involves: (a) chlorinating a compound of the formula: <CHEM> where X<1>, X<2>, R<1>, R<2>, and the squiggly line are as above, using triphosgene in the presence of an organic base to obtain the compound of the formula: <CHEM> where X<1>, X<2>, R<1>, R<2>, and the squiggly line are as above; and (b) reacting the compound of formula 3 with a salt of diphenyl phosphine oxide to obtain the compound of formula 1. Each of the above steps (a) and (b) are individually useful.</p> |