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The products of the insertion reactions of a number of tin(ll) compounds SnXa (X = Cl. Br, 1, NCS, HCOa, and AcO) with [(w-C,H,)Fe(CO),],and (w-C,H,) Fe(CO.J,CI are compared with those from replacement of CI from [(n-C5H6) Fe(CO),],*SnCI, and (n-C,H,) Fe(CO),SnCI,.The llaSn Mossbauer parameters of both series of compounds [(n-C6HB)Fe(C0)2]2*SnX2 and (w-C6H5)Fe(CO),*SnX3 (X = CI, Br, I, NCS, HCO,, and AcO) show that the use of tin bonding electrons is dominated by the Sn-Fe bond. The trends in chemical isomer shift and quadrupole splitting can be explained with reference to the very short Sn-Fe bond lengths in these materials.The positive sign for e29Q can also be explained in terms of a high p-electron density on the tin atom in the direction of the Sn-Fe bond. The i.r. for the products of the insertion reactions are also presented. SEVERAL x-cyclopentadienyl iron carbonyl complexes containing the tin-iron bond have been prepared and compounds of the type (X-C~H~)F~(CO),*S~R, (R = Cl,,+ Br,3s5 I,q5 Me? Et,, and Ph2*) and [(x-C5Hs)-Fe(CO)d,*SnR1, (R1 = C1,3j6 Br? I,8 Me: Et,&' Ph,7 NCS,7,8 AcO,' SEt,' C5H5,7 OH,'have been reported. Some of these complexes can be prepared from either tin@) 3,5s6 or tin(1v) 2,3,7 starting materials and there is apparently no difference in the nature of the products from the two types of re: action.The crystal structures of the following compounds are known: (x-CsHs)Fe(CO),*SnR, (R = Cl,9 Br,s or Ph lo) and [(x-CsHs)Fe(CO)J3*SnR', (R' = Cl, ' C5H,,12 and NO, 14). In each case the tin atom is in a distorted tetrahedral environment in which the bonds to the iron atoms are very short (2-46-2-60 A) while those to the ligands are longer than the sums of the appropriate covalent radii. The bond angles in the tin environment are severely distorted from the ideal tetrahedral angles. These features can be explainedll in terms of an increase in the s-character of the tin orbitals used in the tin-iron bond formation with a corresponding increase in the p-character of the orbitals forming the other bonds with tin. Bryan and his co-workers have pointed out that in the (x-C,H,)Fe(CO),*SnX, complexes, the two halide moieties (-SnC1, and -SnBr,), differ in their conformations about the Sn-Fe bond axis and also differ in this respect from both of the conformationally independent molecules in the unit cell of (x-C,H,)Fe-(CO),*SnPh,. They interpret these differences as being a strong indication of free rotation about the metalmetal bond. This and the values of the Sn-Fe distances

Lithium deuteride has been prepared by the direct combination of lithium and deuterium at 700°, the deuterium having been obtained from the oxide by the use of magnesium. The isotopic and chemical purity of the product have been determined. Lithium aluminium deuteride has been prepared from lithium deuteride and aluminium bromide.

~[ R u ( N H ~) ~( H ~O ) ] ~' + [(NH~),Ru-C-CH]+ + 6H++ 6[ Ru( NH3)5( H20)l3' + 2CH4(1)The catalytic activity of RuCl,-phenanthrolines for the epoxidation of stilbenes by 10, or C10-can be modulated by using phenanthrolines bearing electron-donating or withdrawing groups. Electron-donating groups lead to the highest conversion rates providing they do not cause steric congestion at the N atoms which can coordinate with Ru." ' [Ru(bipy),]C12 in HCON(CH3)2/(HOCH2CH2)3N is an efficient homogeneous catalyst for the photochemical reduction by visible light of CO, to HCO,. Using 13C02 and n.m.r. spectroscopy the disappearance of the 13C02 signal and the simultaneous increase in the H13C02 resonance was monitored. G.c. analysis showed that H2 was also formed photolytically.'7" The photolysis reactions of [Ru(CO),R(q5-C,H5)] (R = Me or Et) have been studied in pentane and C2H,-doped solution(-30 "C) and by matrix(CH,, N,, or CO at 12 K) and C2H4-doped matrix isolation techniques."" p3-Ethylidyne ligands bound to electron-rich Ru3 centres are activated towards deprotonation. Thus oxidation of [Ru3(p3-CMe)(p-CO),( q5-C5Me5),] yields [ Ru3(p3-CMe)(p-CO),( q5-C5Me5),]"' ( n = 1 or 2). For n = 2, the complex slowly deprotonates to give the p3-vinylidene cation [Ru,(p,-CCH,)(p.-CO),( q5-C5Me5)3]' which is highly reactive towards nucleophiles, regenerating the starting material witM NaBH,, and reacts with LiMe to form [Ru3(p3-CEt)(p-C0),( q5-C5Me5),] completing a p3-CMe to p,-CEt homologation.'8b The cyano-complexes [ Ru( q5-C5H5)( PPh3),CN] and [Ru( q5-C5H5)(dppe)(CN)] react in KCN/MeOH with the corresponding Ru-Cl complexes, and with [Fe( q5-C5H5)(dppe)Br], to give [ q5-C5H5)L2Ru(p-CN)RuL:(q5-C5H5)]+ (L = L' = PPh,; L = PPh,, L: = dppe; L2 = dppe, L' = PPh,; L2 = L: = dppe), and the mixed Fe-Ru cation [(q5-C5H5)(dppe)Ru(p-CN)Fe(dppe)(q5-C5H5)]+. The Ru, complex (L = dppe, L' = PPh,) contains the " ( a ) Y . Degani and I.