Insertion of heteroallenes into the rhenium–hydride bond

Dithioformato [Re{η2-SC(H)S}(NO)P3]BPh4 (1), thioformamido [Re{η2-RNC(H)S}(NO)P3]BPh4 (2) (R = Et, p-tolyl), formamido [Re{η2-PhNC(H)O}(NO)P3]BPh4 (3) and formamidinato [Re{η2-p-tolylNC(H)Np-tolyl}(NO)P3]BPh4 (4) (P = PPh2OEt) complexes were prepared by allowing the hydride ReH2(NO)P3 to react first with triflic acid and then with the appropriate heteroallene CS2, RNCS, PhNCO and p-tolylNCNp-tolyl. Treatment of the ReH2(NO)L(PPh3)2 [L = P(OEt)3, PPh(OEt)2] and ReH2(NO)(PPh3)3 hydrides first with triflic acid and then with isothiocyanate RNCS (R = Et, p-tolyl) gave the [Re{η2-RNC(H)S}(NO){P(OEt)3}(PPh3)2]BPh4 (5, 6) and [Re(η2-RNC(H)S)(NO)(PPh3)3]BPh4 (7) derivatives. Depending on the nature of the phosphite, instead, the reaction of ReH2(NO)L(PPh3)2 and ReH2(NO)(PPh3)3 hydrides first with CF3SO3H and then with isocyanate R1NCO (R1 = Ph, p-tolyl) gave the chelate [Re{η2-R1NC(H)O}(NO){P(OEt)3}(PPh3)2]BPh4 (8) and [Re{η2-R1NC(H)O}(NO)(PPh3)3]BPh4(10) complexes with P(OEt)3 or PPh3, while the η1-coordinate [Re{η1-RNC(H)S}(NO){PPh(OEt)2}2(PPh3)2]BPh4 (9) derivative was obtained with the PPh(OEt)2 phosphite ligand. η1-Coordinate dithioformato [Re{η1-SC(H)double bond; length as m-dashS}(NO){PPh(OEt)2}2(PPh3)2]BPh4 (11) and formato [Re{η1-OC(H)double bond; length as m-dashO}(NO){PPh(OEt)2}2(PPh3)2]BPh4 (12) complexes, as well as the formamidinato [Re{η2-p-tolylNC(H)Np-tolyl}(NO){P(OEt)3}(PPh3)2]BPh4 (13) derivative were also prepared.