Photochemical reaction of Re2(CO)10 with tetramethylthiourea;: structural characterization of two novel pentarhenium carbonyl complexes containing sulfide and tetramethyldiaminocarbene ligands, [Re5(CO)17(μ-R)(μ4-S)2{C(NMe2)2}2] (R = SH or OH)

Photochemical reaction of [Re-2(CO)(10)] with tetramethylthiourea [S=C{(NMe2)(2)}] has led to the cleavage of the S=C bond yielding two novel rhenium carbonyl compounds [Re-5(CO)(17)(mu-R)(mu(4)-S){C(NMe2)(2)}(2)] (R = SH 8 or OH 9). The complexes have been characterised by spectroscopic methods and X-ray crystallography, The structure of 8 is based on a distorted Re3S3 octahedral cluster with meridonal arrangement of the three Re and three S atoms. Two of the S atoms are each bound to three Re atoms at the centre and also bonded to a terminally placed Re(CO)(4){C(NMe2)(2)} moiety; the third S atom belongs to a SH group and bridges a pair of the meridonal Re atoms, Only two of the meridonal Re atoms lie within Re-Re bonding distance indicating that Re-Re bonds in [Re-2(CO)(10)] have also been cleaved during the reactions. Compound 9 is isostructural with 8, with the OH group replacing the SH group. (C) 1998 Elsevier Science S.A. All rights reserved.