Northern–Southern Route to Synthetic Bacteriochlorins
作者:Yizhou Liu、Jonathan S. Lindsey
DOI:10.1021/acs.joc.6b02334
日期:2016.12.2
was prepared in five steps from an α-halopyrrole and a 2,2-dimethylpent-4-ynoic acid. The first three steps follow Jacobi’s synthesis of dihydrodipyrrins: Pd-mediated coupling to form a lactone–pyrrole, Petasis reagent treatment for methenylation, and Paal–Knorr type ring closure to form the 1,2,2-trimethyl-substituted dihydrodipyrrin. Subsequent steps entail conversion of the 1-methyl group to the