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Reaction between the nickel(II) species [[graphic omitted]F2(CNR)2](R = But or Pri) and dimethylamine, diethylamine, t-butylamine, pyrrolidine, or morpholine affords monocarbene complexes [[graphic omitted]F2(CNR){C(NHR)NR′2}]; the structures were established by i.r. and n.m.r. spectroscopy. Analogous reactions occurred with [[graphic omitted]F2(CNBut)2], [[graphic omitted](CNR)2](M = Ni, Pd, or Pt; R = But or Pri), [[graphic omitted](CF3)(CNBut)2], and [[graphic omitted](CN)2(CNBut)2] to give the corresponding monocarbene complexes.

Reaction of 9α-fluoro-corticosteroids with NN-dialkylaminosulphur trifluorides gives Δ11-9α-fluoro-steroids (2a,b); a single-crystal X-ray analysis of (2a) is reported.

One-step reduction of PtCl2 to platinum(0) cluster complexes [Pt4(CO)5L4], followed by oxidative addition with Mel, provides a route to new platinum(II) complexes [Pt(CO)L(I)Me](where L is a phosphorus ligand). These react with uncharged ligands L′ to give carbonyl substitution or insertion products or a mixture of both. Both electronic and steric effects help to determine the type of product obtained and, in the case of the insertion reactions, the position of equilibrium between the complexes [Pt(CO)L(I)Me] and [PtLL′I(COMe)].

Icosahedral 2,4-dicarba-1-ferraboranes with η6-bonded benzene, toluene, o-xylene, or naphthalene ligands have been synthesised in moderate yields by reaction of [Fe(cod)(η5-C5H5)](cod = cyclo-octa-1,5-diene) with 2,3-Me2-2,3-C2B9H9 in the presence of the appropriate arene. In addition, the toluene derivative, closo-[1-(η6-C6H5Me)-2,4-Me2-1,2,4-FeC2B9H9](2), has also been obtained by treatment of the carbaborane with [Fe2(µ-η-C6Me6)(η5-C5H5)2] in toluene. Reaction of [RuCl2(η6-C6H6)2] with Tl[TlC2B9H11] affords closo-[3-(η6-C6H6)-3,1,2-RuC2B9H11](7). Complexes (2) and (7) have been characterised by single-crystal X-ray diffraction. Crystals of (2) are orthorhombic, space group Pna21, with a= 21.793(4), b= 8.6274(15), c= 8.636(3)A, and Z= 4; R= 0.0499 for 1 676 reflections. Complex (7) is also orthorhombic, space group Pnam, with a= 18.477(2), b= 9.191(4), and c= 7.704(1)A, and Z= 4; R= 0.0223 for 1 723 data. Both species have slightly distorted Icosahedral cage geometries and overall Cs molecular symmetry, space group imposed for (7). The naphthalene derivative [1-(η6-C10H8)-2,4-Me2-1,2,4-FeC2B9H9] undergoes substitution of the arene ligand by CO at 100 bar and 50 °C, to afford the complex [1,1,1-(CO)3-2,4-Me2-1,2,4 FeC2B9H9].

Study of the reactions [Pt(CO)(PPh3)(I)Me]+ L′→[Pt(PPh3)(L′)I(COMe)][L′= AsPh3,As(p- MeC6H4)3,AsMe(o-MeC6H4)2, and SbPh3] indicates that the first, and largely rate-controlling, step involves neither the incoming ligand nor the solvent, in sharp contrast to related reactions of alkyl carbonyl complexes of other metals and to the normal pattern of ligand-substitution reactions of platinum(II) complexes. This step is thought to involve formation of the intermediate [Pt(PPh3)I(COMe)], which then reacts rapidly with the ligand L′. The apparent change in kinetic behaviour when one or more phenyl groups in the phosphine ligand of the starting material are replaced by o-tolyl groups is believed to be due to a large drop in the rate constant for reaction of the intermediate with ligand L′, arising from crowding caused by the o-tolyl substituents.

Treatment of the complexes Pt[CF2:CF(CF3)]L2[L = PPh3, PPh2Me, (Ph2PCH2)2, or AsPh3] with stannic chloride yields products dependent on the nature of L. With PPh2Me or AsPh3, perfluoropropene is displaced, but with PPh3 or diphos the vinylplatinum compounds trans-PtCl[CCl:CF(CF3)](PPh3)2 and PtCl[CF:CF(CF3)](diphos) are formed, respectively. Reaction of SnCl4 with Pt(C2F4)L2(L = PPh3, PPh2Me, or AsPh3) or with Pt[trans(CF3)CF:CF(CF3)](AsPh3)2 leads to displacement of the fluoro-olefin and formation of PtCl2L2. In contrast, the tin halide reacts with Pt[trans(CF3)CF:CF(CF3)]L2[L = PPh3, PPh2Me, or (Ph2PCH2)2] to yield vinylplatinum compounds cis-PtCl[transC(CF3):CF(CF3)]L2. A mechanism for the C–F bond cleavage and stereospecific nature of the reactions is proposed.

Der Mechanismus der Reaktionen der Komplexe (I) mit dem Diazomethan (II), die zu den Perfluoracetonazin-Komplexen (III) fuhren, wird untersucht und diskutiert.