Reaktionen am koordinierten Trichlormethylisocyanid. II. Cyclische Dithio- und Diaminocarbene

Article abstract of DOI:10.1016/0022-328X(81)80009-5

Cr(CO)5CNCCl3 (1) and 1,2-dithioles in the presence of triethylamine react with cleavage of the CN triple bond to give the 1,3-dithiolane-2-ylidene complexes (R=H (2a), Me (2b)); the other fragment, NCCl3 has been found in the by-products 2-imino-1,3-dithiolane (3) and triethylammonium chloride.The diamines H2NCH2CHRNH2 (R=H, Me), H2NCH2CH2NHMe, and H2N(CH2)3NH2, by analogy, give cyclic diaminocarbene species, while functional isocyanides in the form of Cr(CO)5CN(CH2)4NH2 (6) (main product) and (OC)5CrCN(CH2)4NCCr(CO)5 (7) result from the reaction of 1 with 1,4-diaminobutane.As a deviant from this reaction scheme, N,N'-dimethyldiaminoethane adds across both electrophilic C-centers in 1 to give carbenoid sevenmembered triazepane ring system of which the crystal structure is reported.In the reaction of 2a with triphenylphosphine CO-substitution occurs with formation of (11), amines, such as H2NCH2CH2OH or H2NCH2CH2OMe, on the other hand, attack the cyclic dithiocarbene ligand in 2a and 11 to give Cr(CO)5CNCH2CH2OH (10) and cis-Cr(CO)4(CNCH2CH2OMe)PPh3 (12), respectively.