Trimerisierung von Propiolsäuremethylester an Dicarbonylbis(phosphordonor)eisen-Komplexen
摘要:
The dinitrogen complex (CO)2L2FeN=NFeL2(CO)2 (L = P(OMe)3 (1a), P(O(i)Pr)3 (1b), PEt3 (1c)) reacts with methyl propiolate under elimination of N2 to yield the corresponding acetylene substitution products [(CO)2L2Fe(eta-2-HC=CCOOMe)] (2) and the prototropic vinylidine complexes [(CO)2 L2Fe=C=C(H)COOMe)] (3). In a subsequent reaction 2,3 inserts two equivalents of methyl propiolate and results in the formation of carbonyl-2,4,6-tris(methoxycarbonyl)hexa-1,3,5-triene-1,5-diyl-bis(phosphorus-donor)iron compounds (4,5a) and a carbonyl-1,3,6-tris(methoxycarbonyl)fulvenebis(triisopropylphosphite)iron complex (6). The complexes 5a,6 were determined by X-ray diffraction analyses.