Crystal structure and coordination chemistry of Cl3SnCH2CH2CH2CO2Et

Abstract The crystal and molecular structure of Cl 3 SnCH 2 CH 2 CH 2 CO 2 Et is reported. Crystals of Cl 3 SnCH 2 CH 2 CH 2 CO 2 Et are monoclinic, space group P 2 1 / c with a 8.0242(5), b 11.571(5), c 13.129(12) A and β 104.54(6)°. The tin atom is 5 coordinate with two chlorines and carbon equatorial and the remaining chlorine and the carbonyl oxygen axial, in a distorted trigonal bipyramidal arrangement: (SnCl) ax 2.382(4) A, average (SnCl) eq 2.310(3), SnC 2.125(12), SnO 2.405(8) A. The six-membered chelate ring is slightly boat-shaped. Coordination of the carbonyl group to tin persists in solution but is broken on complexation to Cl 3 SnCH 2 CH 2 CH 2 CO 2 Et by strong nitrogen donors (2,2′-bipyridyl, 1,10-phenanthroline and pyridine (2 moles)). Comparison of the formation constants for adducts of Cl 3 Sn(CH 2 ) n CO 2 Et (A, n  2 or 3), both chelates with monodentate donors, D, suggests comparable acceptor strengths for A ( n  2) and A ( n  3) for 1/1 adduct formation but that A ( n  2) is a weaker acceptor for 2D/A formation.