SYNTHESIS AND METALATION OF FERROCENYLIMINES DERIVED FROM LIGATING DIAMINOHETEROARENES

A regioisomeric mixture of 1,1'-didodecylferrocenedicarbaldehydes 3 wa s prepared from the reaction of a regioisomeric mixture of 1,1'-didode cyldilithioferrocenes and dimethylformamide. Three ligating heteroarom atics were synthesized each containing two amino substituents: 5,5'-di amino-2,2'-bipyridine and 5,5 ''-diamino-2,2': :6',2 ''-terpyridine we re prepared from appropriate dinitro compounds by reduction with palla dium on charcoal-hydrazine hydrate. The reaction of 2-cyano-5-nitropyr idine and hydrazine hydrate gave an isolable amidine derivative and th is was transformed with hydrazine in a separate reaction under more fo rcing conditions into (5-amino-2-pyridyl)-1,2-dihydro-1,2,4,5-tetrazin e. The latter was converted into the tetrazine by oxidation (2,3-dichl oro-5,6-dicyano-1,4-benzoquinone) and then trifluoroacetylated [(CF3CO )(2)O] to give the bis(trifluoroacetylamino) derivative. Diels-Alder r eaction of the latter with dodec-1-yne afforded ecyl-3,6-bis[5-(triflu oroacetylamino)-2-pyridyl]py which was deprotected (K2CO3) to give the corresponding diamine. Bis(ferrocenyl) Schiff bases were prepared fro m ferrocenecarbaldehyde and the appropriate diamine in either uncataly sed or acid-catalysed condensations. Tetracarbonylmolybdenum complexes were prepared by treating the appropriate diamines with molybdenum he xacarbonyl. Reaction of one of these complexes with ferrocenecarbaldeh yde gave a heterobimetallic complex.