Chemistry of the cyclopentadienylmetal Carbonyls V. (A) reactions of cyclopentadienylmolybdenum and-tungsten tricarbonyl halides with group va donor ligands : (B) cationic cyclopentadienylmolybdenum and -tungsten carbonyl derivatives with group va donor ligands

Abstract

The reaction of C 5H 5Mo(CO) 3Cl and triphenylphosphine gives a mixture of C 5H 5Mo(CO) 2[(C 6H 5) 3P]Cl and C 5H 5Mo(CO)[(C 6H 5) 3P] 2Cl; C 5H 5Mo(CO) 3X (X = Br, I) and C 5H 5W(CO) 3Cl react with triphenylphosphine giving monosubstitution only. With triphenylarsine and -stibine C 5H 5M(CO) 3X (M = Mo, X = Cl, Br, I; M = W, X = Cl) monosubstitution is found to occur. The reaction of 1,2-bis(diphenylphosphino) ethane (diphos) and C 5H 5Mo(CO) 3Cl gives C 5H 5Mo(CO)(diphos)Cl and C 5H 5Mo(CO) 2(diphos) +Cl -. The reactions of C 5H 5Mo(CO) 3I and C 5H 5W(CO) 3Cl and diphos lead to C 5H 5M(CO) 2(diphos) +X - and [C 5H 5M(CO) 2X] 2-μ-diphos. The reactions of C 5H 5Mo(CO) 3X(X = Cl, Br, I) and C 5H 5W(CO) 3Cl and bipyridine (bipy) or o-phenanthroline ( o-phen) give C 5H 5M(CO) 2 +X - and C 5H 5M(CO) 2( o-phen) +X - (M = Mo, W) as the only products of these reactions. It is suggested that the chelating ability of a ligand is sometimes important in determining whether an ionic derivative is to be formed. Reactions between the compounds C 5H 5M(CO) 3Cl or C 5H 5M(CO) 2LCl [M = Mo, W; L = (C 6H 5) 3P, (C 6H 5) 3As], a Group VA donor molecule or carbon monoxide, and AlCl 3 have been studied. From such reactions the compounds C 5H 5M(CO) 3L + AlCl - 4 and C 5H 5M(CO) 2L + 2AlCl - 4 [M = Mo, W; L = (C 6h 5) 3P, (C 6H 5) 3As, CH 3CN] were obtained. The compound C 5H 5Mo(CO)(CH 3CN)[(C 6H 5) 3P] + 2AlCl - 4 was obtained from C 5H 5Mo(CO)[(C 6H 5) 3P] 2Cl, CH 3CN and AlCl 3. All cations were eventually characterized as hexafluorophosphate salts.