Graham Turner

Studies of the rhenium oxygen bond—V. The vibrational spectra and force constant analysis of K3ReO2(CN)4, K2ReO2(13CN)4 and K3Re18O16O(CN)4 and some comments on the vibrational spectra of Re2O3(CN)84−

Abstract The i.r. spectra (4000-50cm −1 ) and laser Raman spectra of solid K 3 ReO 2 (CN) 4 , K 3 ReO 2 ( 13 CN) 4 (99% 13 C enriched), and K 3 Re 18 O 16 O(CN) 4 (20% 18 O enriched) have been measured. An assignment of the vibrational frequencies for the D 4h ion has been made. A normal coordinate analysis was carried out. The refined force constants, and potential energy distributions are tabulated. A symmetry factoring treatment of Re-O force constants has also been shown to be valid for the ReO 2 (CN) 3− 4 ion, and has been used for the Re 2 O 3 (CN) 4− 8 ion.

Structures of square-pyramidal acyl and octahedral alkyl intermediates in the decarbonylation of acid halides by chlorotris(triphenylphosphine)rhodium(I)

Oxidative addition of acetyl chloride to the compound [RhCl(PPh3)3] leads to the formation of two acetyl- and one methyl-rhodium species, all isomeric, before reductive elimination of methyl chloride occurs to give [RhCl(CO)(PPh3)2]. The structures of all the compounds have been determined using i.r. and both 1H and 31P n.m.r. spectroscopy. The effects of changing the nature of the acid halide and the tertiary phosphine have been determined as have thermodynamic parameters for the ‘carbonyl-insertion’ reactions involved. The X-ray crystal structure of the compound [RhCl2(COCH2CH2Ph)(PPh3)2] demonstrates essentially a square pyramid with trans-basal chlorides, trans-basal phosphines, and an apical acyl group.