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Reactions between the compounds [W~(H)(O-i-Pr)712 and WZ(H)(O-C-C~H~)~(HNM~~) and olefins, alkynes,allene, 1,3-butadiene, ketones, and nitriles have been studied. Of the olefins, only ethene forms a kinetically persistent compound, and W2(0-c-C5H9)7(q2-C2h)(q1-C2H5) has been fully characterized. Other a-olefins are slowly isomerized to intemal olefins, but, in the presence of added hydrogen, hydrogenolysis to give the alkane is kinetically preferred. Reactions employing allene and/or 1,3-butadiene are more complex as a result of ligand scrambling, and only the compound W~(O-C-C~H~)&-CHZCCHZ) has been fully characterized. With aldehydes and ketones, insertion into the metal hydride generally proceeds to give alkoxide ligands, and the complex W2(0-c-C5H9)8(q2-0-c-c5H8) derived from the reaction involving W:!(H)(O-C-C~H~)~(HNM~~) and cyclopentanone has been fully characterized. With benzophenone, an adduct is formed, which in the solid state and in solution is believed to have a terminal hydride and is formulated as W2(H)(OR)7(q2-OCPh2), an analogue of the W2(q1-C2H5)(q2-C2&) complex. No single product from the reactions between ethyne and a Wz@-H)-containing compound has been fully characterized, but spectroscopic evidence is strongly in favor of a reaction sequence involving (i) ethyne adduct formation, (ii) insertion to form a p-vinyl ligand, and (iii) further addition of ethyne and hydride to give a 2-butenylidene complex W~( O R ) I~( C~H~) . With MeCECMe and [W2(H)(O-i-Pr)7]2, the previously characterized compound W2(0-i-Pr)6@-C4Me4)(q2-c2Me2) is formed with the elimination of i-PrOH and propene. The reactions employing nitriles give products derived from hydride reduction of the coupled nitriles, and the compound W2(0-i-Pr)7@-q1-N,ql-N-NCPhCPhN(H)) has been structurally characterized. Crystal data for W2(0-c-CgH9)7(q2-C2&)(q1-C2H5) at -155 "C: P21/a, a = 20.237(5) A, b = 9.938(5) A, c = 21.660(5) A, p = 113.91(1)", Z = 4. Crystal data for W~( O -C -C~H~)~@ -C H~C C H~) at -171 "C: P21/n, a = 18.070(5) A, b = 24.432(6) A, c = 9.848(2) A, p = 90.19(1)", Z = 4. Crystal data for Wz(0-cC5Hg)8(q2-0-c-C5H8) at -175 "C: P21/c, a = 10.618(1) A, b = 20.824(2) A, c = 22.154(5) A, p = 115.22(1)", Z = 4. Crystal data for W2(H)(O-i-Pr)7(q2-OCPh2) at -172 "C: P21/n, a = 11.899(5) A, b = 19.928(8) A, c = 15.956(7) A, p = 91.61(2)", Z = 4. Crystal data for W2(O-i-Pr)7(p-q1-N,q'-N-NCPhCPhN(H)) at = -171 "C: Pi, a = 18.688(4) A, b = 22.186(5) A, c = 10.368(2) A, a = 94.39(1)", / 3 = 92.42(1)", y = 68.5(1)", Z = 4.

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Tertiary phosphine substituted metal carbonyl complexes are generally very well known (1) although there have been only a few studies in this area involving ferrocenylphosphines such as PFc,Ph,-,, n = 1-3 (2-8) (FcH = Fe(q-CSH5)2), and 1,l'-disubstituted ferrocene derivatives such as dppf, l,lf-bis(dipheny1phosphino)ferrocene (2,9,10). Phosphine derivatives are generally prepared by direct reaction of the phosphine with the metal carbonyl. Sometimes, and especially in the case of Fe3(C0)12, cluster breakdown is found so that the isolated products are phosphine derivatives of mononuclear carbonyls, e.g. (Fe(C0)4(PR3) and Fe(C0)3(PR3)2 (3,5, 8, 1 1 -16). Reactions of this type involving R u~( C O )~~ usually afford trinuclear products (17)(18)(19)(20). Photosubstitution of R u~( C O )~~ seems to occur largely from higher energy states whereas photofragmentation involves the lowest excited state (20). The use of the radical anion, sodium diphenylketyl, as a catalyst has recently greatly facilitated the preparation of a wide range of derivatives Ru3(CO),,-,L,, n = 1-4, because the reactions are essentially stoichiometric (21). The method is also useful for the synthesis of derivatives of Fe3(C0)12. Salts of the bis(tripheny1phos-phine)iminium ion, ppn+, are also effective catalysts (22).In view of the success in trapping a benzyne fragment on a metal cluster from reactions of arylphosphines with M3(CO),2 'Author to whom correspondence may be addressed.(M = Ru, 0 s ) (23-25) directly or stepwise, we have initiated a study of the corresponding reactions of ferrocenylphosphines in the hope that this will lead to the trapping of a ferrocyne fragment. The present paper describes the synthesis of some derivatives of Fe3(C0)12 and R U~( C O )~~, because of our interest in their pyrolysis products, and the crystal structures of R u~( C O )~ I(PF~Ph2) and Ru3(CO) ,o(p-dppf). The thermal decomposition of R U~( C O )~, , ( P F C P~~)~ to a benzyne complex has been reported (25). Experimental sectionReactions were carried out in a nitrogen atmosphere by using standard Schlenk procedures. Solvents were dried and distilled before use. Separation of products was usually achieved by column chromatography on Florisil or neutral alumina (activity I) by using petroleum ether (35-60°C bp fraction)/diethyl ether mixtures as eluent. I H NMR spectra were recorded from CDC13 solutions by using Bruker WH400 or WP80 and Varian XL300 instruments. Infrared spectra, usually of C6H12 solutions, were run on a Bowman Fourier Transform or a Perkin Elmer 589 spectrometer. Mass spectra were obtained from a Kratos MS 50 instrument; only peaks with high m / e values are listed and electron impact ionization was used unless otherwise stated. Elemental analyses were determined by Mr. P. Borda of the Chemistry Department, University of British Columbia. Melting points were measured by using a Kofler microheating stage and are uncorrected. A Hanovia lOOW lamp (903A-1) was used for UV irradiations. To minimize