Eberhard Wilhelm

Chemie polyfunktioneller moleküle: LXXVII. Das reaktionsverhalten von bis(diphenylphosphino)amin gegenüber di-μ-chloro-bis[dicarbonylrhodium(I)]☆

Abstract This paper describes the direct synthesis of the A-frame complex Rh 2 (μ-CO)(μ-Ph 2 PNHPPh 2 ) 2 Cl 2 ·CH 3 OH·O(C 2 H 5 ) 2 (IV′) from [Rh(μ-Cl)(CO) 2 ] 2 and Ph 2 -PNHPPh 2 (I). The intermediates formed, [Rh 2 (μ-CO)(μ-Cl)(μPh 2 PNHPPh 2 ) 2 (CO) 2 Cl·0.5O (C 2 H 5 ) 2 (Va), Rh 2 (μ-CO)(μ-Cl)(μPh 2 PNHPPh 2 ) 2 (CO)(Cl)·0.5O(C 2 H 5 ) 2 (VI), and the by-product [Rh(CO)(Cl)(Ph 2 PNHPPh 2 )·(1–2) CH 3 OH] n (VII), were isolated and characterized. Compound IV′ reacts with CO to yield Va, which undergoes a metathesis reaction with NaBPh 4 or NH 4 PF 6 , to give [Rh 2 (μ-CO)(μ-Cl)(μ-Ph 2 PNHPPh 2 ) 2 (CO) 2 ]BPh 4 ·CH 3 OH (Vb) and [Rh 2 (μ-CO)(μ-Cl)(μ-Ph 2 PNOPPh 2 ) 2 (CO) 2 ]PF 6 (Vc). The reaction of [Rh(μ-Cl)(CO) 2 ] 2 with I in a molar ratio of 3 4 , yields (Rh 2 (μ-CO)(μ-Cl)-(μ-Ph 2 PNHPPh 2 ) 2 (CO) 2 ][Rh(CO) 2 Cl 2 ]·2CH 3 OH (Vd). The reaction of [Rh(μ-Cl)(CO) 2 ] 2 with I in a closed tube (molar ratio 1 2 ) yields [Rh 2 (μ-CO)(μ-Cl) (μ-Ph 2 PNHPPh 2 ) 2 (CO) 2 ]Cl·CH 3 OH (Va′). The compound [Rh 2 (gm-Cl)-(μ-Ph 2 PNHPPh 2 ) 2 (CO) 2 ]BPh 4 ·CH 3 OH (VIII) is obtained from Vb in methanolic solution with CO elimination. From a solution of VIII in CH 2 Cl 2 , [Rh 2 (μ-Cl)(μ-CH 2 Cl 2 ) (μ-Ph 2 PNHPPh 2 ) 2 (CO) 2 ]BPh 4 -O(C 2 H 5 ) 2 (IX) precipitates on adding diethyl ether. Red IX in methanolic solution converts back to the yellow VIII. The structures of the new compounds are determined on the basis of 31 P{ 1 H} NMR, 1 H NMR, IR, ESR and MS spectroscopic and conductometric data.