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The reaction of LiN(SiMe2CH2PPh2)2 with RuCl2(PPh3)3 leads to the formation of the ruthenium amide complex RuCl(PPh3)[N(SiMe2CH2PPh2)2]. This complex reacts with H2 to form two isomeric amine-hydride derivatives of the formula RuCl(PPh3)H[NH(SiMe2CH2PPh2)2]. Reaction of RuCl(PPh3)[N-(SiMe2CH2PPh2)2] with MeLi, Me3SiCH2Li, or H2C=CHCH2MgCl does not lead to the expected hydrocarbyl derivative; rather, ortho metalation occurs to generate Ru(C6H4PPh2)[N(SiMe2CH2PPh2)2]. Attempts to displace the PPh3 ligand of RuCl(PPh3)[N(SiMe2CH2PPh2)2] with PEt3 lead to the formation of RuCl- (C6H4PPh2) [NH(SiMe2PPh2)2], having an amine ligand and the ortho-metalated phenyl group. The complex RuCl(C6H4PPh2)[NH(SiMe2CH2PPh2)2] crystallizes in space group P21/n with a = 9.8385 (5) A,b = 29.561 (1) A,c = 20.8665 (9) A, 8 = 101.683 (4)°, V = 5942.2 (5) A3, and Z = 4. Transformation of an amide linkage to an amide via H2 activation or ortho metalation is apparently driven by the formation of an intramolecular hydrogen bond between the amine hydrogen and the coordinated chloride; the N-H-Cl distance is 2.76 (6) A, which is shorter than the expected van der Waals separation of 3.0 Á.

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An exercise in molecular modeling, suitable for a third- or fourth-year course in organometallic or inorganic chemistry, is presented in which the effects of the metal center, the metal charge, and the electron-withdrawing properties of co-ligands upon the degree of π backbonding to carbonyl ligands are demonstrated. The ν CO values are calculated, along with C–O bond orders for a series of model compounds to demonstrate each effect. The calculated values are also compared with experimental ones.

An undergraduate exercise in computational chemistry that investigates the energy barrier for pyramidal inversion of amines and phosphines is presented. Semiempirical calculations (PM3) of the ground-state and transition-state energies for NR1R2R3 and PR1R2R3 allow for the determination of the activation energy for pyramidal inversion. Various factors affecting the inversion activation energy are considered. The exercise can be done easily in a 3-h lab on a standard laptop running Spartan or Spartan Student or as a homework assignment.