Triphenylantimony dioximates Ph3Sb(ON=CHR)2 (R = C6H4NO2-2, C6H4NO2-3, C6H4Br-2, C6H4Br-3, or C4H2ONO2-5): Synthesis and structure

Abstract

Triphenylantimony dioximates Ph₃Sb(ON=CHR)₂ (R = C₆H₄NO₂-2 (I), C₆H₄NO₂-3 (II), C₆H₄Br-2 (III), C₆H₄Br-3 (IV), and C₄H₂ONO₂-5 (V)) have been synthesized by the reaction between triphenylantimony and oximes in diethyl ether in the presence of tert-butylhydroperoxide (1: 2: 1 mol/mol/mol). The antimony atoms in I–V have a distorted trigonal bipyramidal coordination. The axial ОSbO angles are 174.8(3)°, 174.4(3)° (Ia, Ib), 175.02(19)° (II), 175.62(9)° (III), 176.34(5)° (IV), and 172.0(4)° (V). The Sb–O and Sb–C bond lengths are 2.046(7)–2.088(6) and 2.075(9)–2.185(8) Å in Ia, Ib, 2.079(5), 2.090(7), and 2.090(7)–2.115(7) Å in II, 2.0712(19), 2.0744(19), and 2.096(3)–2.109(3) Å in III, 2.065(4), 2.083(3), and 2.089(5)–2.140(5) Å in IV, and 2.088(7) and 2.110(10)–2.116(14) Å in V. The Sb···N intramolecular distances (2.779(10)–2.900(9) Å) are ~1 Å shorter than the antimony and nitrogen van der Waals radii in sum.