Three new dicarboxylatodirhenium(III) compounds and their structures: a structure type not previously seen

Abstract Three new structures of compounds containing the Re 2 (O 2 CR) 2 X 4 unit are reported and two are shown to contain features rarely or not previously observed. Reaction of trimeric ReCl 3 and PhCOONa in THF under reflux conditions for 24 h gave dark-green orthorhombic crystals of the THF solvate cis -Re 2 (O 2 CPh) 2 Cl 4 (THF) 2 ·THF ( 1 ). The crystals belong to the space group Pbcm with unit cell dimensions a = 8.867(2), b = 19.851(4), c = 18.022(4) A, V = 3172(2) A 3 , and D calc = 2.037 g/cm 3 for Z = 4. The structure was refined to R = 0.037 and R w = 0.046 for 1825 reflections having I >3σ( I ). Reaction of [(n-C 4 H 9 ) 4 N] 2 Re 2 Cl 8 and NaF in acetonitrile under reflux conditions for 4 days followed by work-up in acetone gave blue, monoclinic crystals of cis -[(n-C 4 H 9 ) 4 N][Re 2 (O 2 CCH 3 )Cl 5 ]· (CH 3 ) 2 CO ( 2 ).The crystals belong to the space group P 2 1 / n with unit cell dimensions a = 11.283(4), b = 13.577(5), c = 21.835(10) A, V = 3345(4) A 3 , and D calc = 1.923 g/cm 3 for Z = 4. The structure was refined to R = 0.056 and R w = 0.066 for 2443 reflections having I >3σ( I ). Compound 3 , [ReCl 2 (dpcp) 2 ][Re 2 (O 2 CPh) 2 Cl 6 ]·CHCl 3 contains the first example of an axially coordinated species with a transoid arrangement of the carboxylate ligands. 3 crystallizes in space group P 1 with a = 13.372(4), b = 14.067(6), c = 10.899(7) A, α = 99.694(5)°, β = 103.030(5)°, γ = 84.501(3)°, V = 1966(3) A 3 , Z = 1. The structure was refined to R = 0.067 and R w = 0.082 for 2648 reflections with I >3σ( I ).