A pale-blue Ir(I) dicarbonyl chloride surface species is obtained by carbonylation of [Ir-(cyclooctene)(2)Cl](2) supported on the silica surface working under. mild conditions (1 atm of CO, room temperature). This species is probably weakly bound to the surface silanol groups. It can be extracted only with weak donor solvents like, acetone and acetonitrile, affording a solution of the dimer [Ir(CO)(2)Cl](2). This dimer can be also obtained by carbonylation under mild conditions of [Ir(cyclooctene)(2)Cl](2) in the latter solvents. Evaporation of the donor solvents transforms [Ir(CO)(2)Cl](2) into a dark-brown, almost black, amorphous carbonyl material, probably polymeric via strong Ir-Ir interactions. Likewise, in nondonor solvents like toluene and pentane, carbonylation of [Ir(cyclooctene)(2)Cl](2) produces. the same insoluble material of formula [Ir(CO)(2)Cl](2). This material may be reversibly dissolved by donor solvating solvents, to form again a solution of the dimer. The acetonitrile solution of [Ir-(CO)(2)Cl](2) is a very convenient starting material for the high-yield preparation of many Ir(I) carbonyl derivatives such as, for instance, [Ir(CO)(2)Cl-2](-), [Ir(CO)(2)(amine)Cl], [Ir(CO)(PPh(3))(2-)Cl], and [Ir(CO)(2)(acac)], where acacH is acetylacetone.
Formation of [Ir(CO)2Cl]x (x = 2, n) Species by Mild Carbonylation of [Ir(cyclooctene)2Cl]2 Supported on Silica or in Solution: A New Convenient Material for the Synthesis of Iridium(I) Carbonyl Complexes / D.M. Roberto, E. Cariati, R. Psaro, R. Ugo. - In: ORGANOMETALLICS. - ISSN 0276-7333. - 13:11(1994 Nov), pp. 4227-4231. [10.1021/om00023a027]
Formation of [Ir(CO)2Cl]x (x = 2, n) Species by Mild Carbonylation of [Ir(cyclooctene)2Cl]2 Supported on Silica or in Solution: A New Convenient Material for the Synthesis of Iridium(I) Carbonyl Complexes
D.M. RobertoPrimo
;E. CariatiSecondo
;R. UgoUltimo
1994
Abstract
A pale-blue Ir(I) dicarbonyl chloride surface species is obtained by carbonylation of [Ir-(cyclooctene)(2)Cl](2) supported on the silica surface working under. mild conditions (1 atm of CO, room temperature). This species is probably weakly bound to the surface silanol groups. It can be extracted only with weak donor solvents like, acetone and acetonitrile, affording a solution of the dimer [Ir(CO)(2)Cl](2). This dimer can be also obtained by carbonylation under mild conditions of [Ir(cyclooctene)(2)Cl](2) in the latter solvents. Evaporation of the donor solvents transforms [Ir(CO)(2)Cl](2) into a dark-brown, almost black, amorphous carbonyl material, probably polymeric via strong Ir-Ir interactions. Likewise, in nondonor solvents like toluene and pentane, carbonylation of [Ir(cyclooctene)(2)Cl](2) produces. the same insoluble material of formula [Ir(CO)(2)Cl](2). This material may be reversibly dissolved by donor solvating solvents, to form again a solution of the dimer. The acetonitrile solution of [Ir-(CO)(2)Cl](2) is a very convenient starting material for the high-yield preparation of many Ir(I) carbonyl derivatives such as, for instance, [Ir(CO)(2)Cl-2](-), [Ir(CO)(2)(amine)Cl], [Ir(CO)(PPh(3))(2-)Cl], and [Ir(CO)(2)(acac)], where acacH is acetylacetone.Pubblicazioni consigliate
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.