84369-18-6Relevant articles and documents
Synthesis, structure, and reactivity of the thioformaldehyde complex [(η5-C5H5)Re(NO)(PPh 3)(η2-H2C=S)]+PF 6-
Buhro, William E.,Etter, Margaret C.,Georgiou, Savas,Gladysz,McCormick, Fred B.
, p. 1150 - 1156 (2008/10/08)
Reaction of [(η5-C5H5)Re(NO)(PPh3)(=CH 2)]+PF6- (2) and S=PPh3 gives a 1:1 mixture of thioformaldehyde complex [(η5-C5H5)Re(NO)(PPh 3)(η2-H2C=S)]+PF 6- (1) and ylide complex [(η5-C5H5)Re-(NO)(PPh3)(CH 2PPh3)]+PF6- (3). However, reaction of 2 and cyclohexene sulfide gives 1 (85-95% after recrystallization). An X-ray structure of 1 (crystal data: monoclinic, P21/c; a = 9.688 (2) A?, b = 18.536 (4) A?, c = 14.895 (s) A?; β= 103.53 (2)°; Z = 4) shows that the η2-H2C=S ligand adopts a conformation that has significant overlap of its π* orbital with the rhenium fragment HOMO and its sulfur terminus syn to the PPh3. Extended Hu?ckel MO calculations on the model compound [(η5-C5H5)Re(NO)-(PH 3)(η2-H2C=S)]+ predict a similar conformational energy minimum. Complex 1 is stable in CD3CN (41 h, 51°C) but rapidly reacts with PPh3 (2 equiv) to give 3 (95%) and S=PPh3 (88%). Reaction of 1 and NaBH3CN gives thiomethyl complex (η5-C5H5)Re(NO)(PPh3)(SCH 3) (5, 85% after recrystallization). The reactivity of 1 is compared to that of formaldehyde complex [(η5-C5H5)Re(NO)(PPh 3)(η2-H2C=O)]+ PF6-, and the mechanisms of the above reactions are discussed.
