The cyclopropyl-containing phosphine di-tert-butyl(cyclopropylmethyl)phosphine, P(t-Bu2CH2- CHCH2CH2, reacts with PdCl2 to afford trans-PdCl2(P(t-Bu)2CH2CHCH2CH2)2. When this complex is refluxed in MeOCH2CH2OH or glacial acetic acid, a cyclometalated dimer, [PdCl(P(t-Bu)2CH=C- (CH3)CH2)]2, is formed, as deduced from spectroscopic and X-ray analysis. This complex crystallizes in the monoclinic space group C2h5P21/n (a = 7.957 (4) Å, b = 15.780 (2) Å,_c = 12.169 (1) Å, and β = 99.11 (2)) with two molecules per unit cell (imposed crystallographic symmetry, 1). The final agreement indices for 2493 reflections having F0 2 > 3σ(F0 2) are R(F) = 0.031 and Rw(F) = 0.041 (136 variables). The five-atom chelate ring PdP°C=C°C is planar to within 0.011 (4) Å with a bond length pattern of PdP = 2.218 (1) Å, P°C = 1.781 (4) Å, C=C = 1.328 (5) Å, C°C = 1.493 (5) Å, and CPd = 2.016 (3) Å. The Pd-Cl distance trans to the P atom is 2.416 (1) Å and that trans to the C atom is 2.457 (1) Å. In the formation of the complex the chelating σ-allyl group probably results from C-C bond activation of the cyclopropyl group.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry