ALKYLATIONS AND THERMAL SIGMATROPIC REARRANGEMENTS OF NICKEL 1-METHYLTETRADEHYDROCORRINS

Nickel 1-methyltetradehydrocorrins react with alkyl halides to yield nickel 19-alkyl-1-methyltetradehydrocorrin salts. In one example in the analogous cobalt series the reaction is similar, although the cobalt 1- methyltetradehydrocorrin must be prepared in situ. When the nickel 1-methyltetradehydrocorrins are heated in o-dichloro-benzene, they undergo a smooth sigmatropic rearrangement to corroles containing a gem-dialkyl grouping at C-2. Similar treatment of a nickel 1-methyltetradehydrocorrin containing no alkyl substituent at C-2 gave the normal nickel corrole.