Ruthenium and osmium porphyrins of the form (por)M(CO) (por = octaethylporphyrinato dianion (OEP), tetratolylporphyrinato dianion (TTP)) react with thionitrites (RSNO) and isoamyl nitrite (RONO) to give the (por)M(NO)(SR) and (por)M(NO)(OR) addition products. Reaction of S-nitroso-N-acetyl-l-cysteine methyl ester with (TPP)Fe(THF)2 (TPP = tetraphenylporphyrinato dianion) gives (TPP)Fe(NO) in high yield. The related reaction of isoamyl nitrite with [(TPP)Fe(THF)2]+ gives the nitrosyl alcohol product [(TPP)Fe(NO)(HO-i-C5H11)]+. The solid state structures of (OEP)Ru(NO)(NACysMe-S) (NACysMe = N-acetyl-l-cysteinate methyl ester), (TTP)Os(NO)(S-i-C5H11), and [(TPP)Fe(NO)(HO-i-C5H11)]+ have been determined by X-ray diffraction.

The aqueous reaction of cobalt(II) sulfate with trimesic acid (H 3 TMA ) 1,3,5-benzenetricarboxylic acid) in the presence of a base yields complexes with the general formula of Co 3 (TMA) 2 . The identity of the base determines the specific structural characteristics of the complexes formed. When sodium hydroxide is used, a novel cobalt(II) coordination polymer,, is produced. Compound 1 contains NaCo 3 (OH) clusters connected via TMA ligands into 1D chains, and 1 crystallizes in the orthorhombic space group Pbca with a ) 18.907(2) Å, b ) 14.565(3) Å, c ) 21.414(4) Å, and Z ) 8. When triethylamine is used, the previously reported 1D zigzag chain coordination polymer, [Co 3 (TMA) 2 (H 2 O) 12 ] n (2), is produced. When tetraethylammonium hydroxide is used, a trinuclear cobalt(II) complex, [Co 3 (TMA) 2 (H 2 O) 14 ]‚4H 2 O (3), is produced that has a structure identical to a segment of the zigzag chain of 2. Compound 3 crystallizes in the triclinic space group P1 h with a ) 6.6542(5) Å, b ) 10.7114(7) Å, c ) 12.3567(7) Å, R ) 99.008(4)°, β ) 102.553(6)°, γ ) 107.344(7)°, and Z ) 1.

The major iron-containing species present during and after the [Cp*Fe(CO) 2 ] 2 -catalyzed allylic amination of olefins by nitrobenzene is a novel cyclic carbamoyl complex 2. Complex 2 is found to be a resting state in the catalytic reaction.

The nonracemic bis(indene) (+)-(1R,2R,4R,5R)-1,4-bis(3′-indenyl)-2,5-diisopropylcyclohexane (10) was synthesized in 60% yield from the addition of indenyllithium to the corresponding bis(methanesulfonate) ester of 2,4-diisopropyl-1,4-cyclohexanediol. Deprotonation of bis(indene) 10 with n-BuLi followed by metalation with TiCl 3 and oxidative workup (HCl, air, chloroform) gave the single stereoisomeric 2,5-diisopropylcyclohexane-1,4-diylbridged bis(indenyl)titanium dichloride 3 in 80% yield. Attempts to form the corresponding bis(indenyl)zirconium dichloride were unsuccessful. Catalytic hydrogenation of bis(indenyl)titanium dichloride 3 gave the 2,5-diisopropylcyclohexane-1,4-diyl-bridged bis(tetrahydroindenyl)titanium dichloride 4 in 76% yield. The solid-state structure of 4 was determined by X-ray crystallographic methods. Nonracemic mixtures of chiral bis(indenyl)titanium dichloride 3 and bis(tetrahydroindenyl)titanium dichloride 4 were examined as catalysts for the pinacol coupling of benzaldehyde in the presence of manganese metal. The enantioselectivities for dihydrobenzoin were 0% with bis(indenyl) 3 and 32% with bis(tetrahydroindenyl) 4 to give the first comparison of enantioselectivities with corresponding bis(indenyl) and bis-(tetrahydroindenyl) complexes. Scheme 1 Scheme 2