Carbonyls phosphine halides

I, Table X) requires tertiary phosphine-nickel halide or tertiary phosphine-nickel carbonyl complexes at 140-170°C. This implies oxidative addition of aromatic halides to nickel, replacement of the halide with amines, and reductive elimination. 

Manganese (continued) carbonyl halides, 3 78, 79-80 complexes with phosphine, etc., 6 10 carbonyls... 

In both the examples given above, there is concomitant loss of one or more neutral ligands. Elimination of CO is the rule in reactions of mononuclear metal carbonyls (e.g., entry 12) and cyclopentadienyl metal carbonyls (e.g., entry 4), but not those of polynuclear carbonyls (e.g., entry 16) or carbonyl halides (e.g., entry 33). Elimination of tertiary phosphines often occurs, especially when more than two molecules are present in the initial complex however, this is not always the case (see entry 24). Clearly, steric requirements and the dictates of the 18-electron rule determine the composition of the product, and normally act in concert when they conflict, as in the case of R3SiRuH3(PR3) (n = 2 or 3 entry 22), variable stoichiometry may result. Chelating diphosphines, with somewhat reduced steric requirements, are usually retained (e.g., entry 19), while complexed olefins are invariably lost the bulky ligand P(cyclohexyl)3 is associated with unusual products (entries 47 and 48). Particular mention may be made of the 17-electron species Cl3SiVH(Cp)2 and (Cl3Si)2V(Cp)2 shown... 

Recently we have been interested in phosphine-containing carbonyl cations of the noble metals (55) such as [M(CO)3(PR3)2X]+ (M = Fe, Ru, Os X = halogen) and [M(CO)2(PR3)2]+ (M = Rh, Ir) which we prepared from the corresponding metal carbonyl halides under atmospheric CO pressure. 

Monomeric complexes provided the earliest examples of Irn species in the red, square oxoaryl phosphines (18-G-VI) although IrBr3(NO)(PPh3)2 and polymeric carbonyl halides [Ir(CO)2X2] were known previously. 

With rhenium carbonyl halides, however, the phosphine gives monosubstitution, with excess carbonyl bromide then eliminating halosilane to give the mixed bridged complex (equation 74)93. 

The important preparative methods, namely, reduction of phosphine metal halide complexes and the hydride-transfer and reverse carbonylation reactions, were discussed in Section I,B,2 and 3. Other routes are incidentally discussed below. 

Natural Products.—A number of one-step olefin syntheses have appeared in which phosphine, alkyl halide, and carbonyl compound are allowed to react together in the presence of a suitable epoxide as the source of base. Among them are the synthesis of ( )-mitorubrin and of the polyene (97) (Scheme 5). ... 

Another area of major interest in the field is that of mixed metal cluster systems. Hieber very early in the study of metal carbonyl chemistry was able to prepare mercury complexes of the type Fe(CO)4(HgCl)2. The related gold ° compounds were prepared in the 1960s by reaction of phosphine gold halides with carbonyl anions. 

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