Chiral tetraphenylcyclopentadienyl complexes of ruthenium and palladium; crystal structure of [Ru(η5-C5Ph4R1*)(CO)2Br](R1*= menthyl)

The compound (–)-bromomenthyltetraphenylcyclopentadiene has been synthesised. It reacts with [Ru3(CO)12] to give [Ru(η5-C5Ph4R1*)(CO)3]Br (R1*= menthyl) which on heating yields [Ru(η5-C5Ph4R1*)(CO)2Br]1. Alternatively complex 1 may be prepared by treating bromoform with [Ru(η5-C5Ph4R1*)(CO)2H], generated from [Ru3(CO)12] and C5Ph4R1*H. A crystal structure of complex 1 shows that the crystals are monoclinic, space group P21(C22, no. 4), Z= 4, with a= 13.783(4), b= 17.799(5), c= 14.974(3)A, β= 107.05(2)°, U= 3512.0 A3., the structure has been refined to R 0.0777 for 3931 unique reflections in the range 3.5 < 2θ < 45°(Mo-Kα radiation). The corresponding complex [Pd(η5-C5Ph4R2*)(η3-C3H5)](R2*= neomenthyl)2 has been synthesised by the reaction of Li[C5Ph4R2*] with [{Pd(η3-C3H5)Cl}2].