87434-76-2Relevant articles and documents
New Efficient Total Syntheses of Derivatives of Protoporphyrin-IX Bearing Deuterated Methyl Groups
Smith, Kevin M.,Pandey, Ravindra K.
, p. 1383 - 1388 (2007/10/02)
New total syntheses of hemins which are regioselectively deuterated in the 1,5 (2), 5 (3) or 8 (4) methyl groups are described.Syntheses of hemins 2 and 3 follow the progression from pyrromethane 12 to t-butyl tripyrrene-carboxylate hydrobromide (17 and 30) and then to a,c-biladiene dihydrobromide (19 and 31), but for reasons of economy in use of labeled monopyrroles, the a,c-biladiene dihydrobromide 40 for hemin 4 is approached in an initially "clockwise" manner by synthesis of a benzyl tripyrrene-carboxylate hydrobromide 37 from the pyrromethane 5.Cyclization of the a,c-biladienes (19, 31, and 40) was accomplished by brief heating in dimethylformamide in the presence of copper(II) chloride.