Formation of Nickel Tetradehydrocorrins and Porphins from Linear Tetrapyrroles of Varied Oxidation Level
Dicker, I.D., David Dolphin, Grigg, R., and Johnson, A.W.
Chemical Commununications (London)
1,19-Dideoxy-1-methylbiladiene-ac dihydrobromides (I, X = H) were prepared and shown to yield porphins when heated in o-Cl2C6H4. Thus, 1,19-dideoxy-8,12-diethyl-1,2,3,7,13,17,18-heptamethylbiladiene-ac-2HBr (II) gave 33% 8,12-diethyl-2,3,7,13,17,18-hexamethylporphin after aerating and heating with o-Cl2C6 H4 at 100 oC for 14 hrs. Compound II treated with piperidine and Ni(OAc)2 in MeOH in air gave 56% Ni 8,12-diethyl-1,2,3,7,13,17,18-heptamethyltetradehydrocorrin. The ability of bilenes to undergo cyclization to tetrahydrocorrins was shown by cyclization (62%) of III to IV.