RING-OPENING OF STRAINED-RING HETEROCYCLES CONTAINING NITROGEN BY AN OSMIUM CLUSTER COMPLEX

The osmium cluster COMPleX Os3(CO)10(mu-NCH2CH2CH2)(mu-H) (1) was obtained in 34% yield from the reaction of Os3(CO)10(NCMe)2 With azetidine. Complex 1 was characterized crystallographically and shown to contain a four-membered NCH2CH2CH2 ring bridging two of the metal atoms via the nitrogen atom. When heated to 125-degrees-C, 1 was transformed to the new complex Os3(CO)10[mu-N=C(H)Et](mu-H) (2; 27% yield) by an opening of the four-membered ring and a hydrogen shift. Crystal data: for 1, space group P2(1)/c, a = 8.793 (2) angstrom, b = 16.265 (2) angstrom, c = 13.766 (4) angstrom, beta = 110.56 (1)-degrees, Z = 4, 1872 reflections, R = 0.039; for 2, space group P1BAR, a = 14.626 (3) angstrom, b = 22.961 (6) angstrom, c = 9.089 (2) angstrom, alpha = 92.73 (2)-degrees, beta = 99.03 (2)-degrees, gamma = 81.52 (2)-degrees, Z 6, 4862 reflections, R = 0.024.