Neutron Diffraction Crystallography of meso-R(H)Sb−Sb(H)R and Reactions of R(H)Sb−Sb(H)R and RSbH2 (R = (Me3Si)2CH) Leading to Tungsten Carbonyl Complexes, Methylstibanes, and Antimony Homocycles

The crystal structure of the meso form of R(H)Sb−Sb(H)R ( 1; R = (Me 3 Si) 2 CH) was studied by single-crystal neutron diffraction at 20 K. 1 or RSbH 2 ( 2 ) reacts with W(CO) 5 THF (THF = tetrahydrofuran) to give meso - and d, l -(OC) 5 W[R(H)Sb−Sb(H)R]W(CO) 5 ( 3 ) or R(H) 2 SbW(CO) 5 ( 4 ). Dehydrogenation of 3 or 4 leads to [RSb SbR]W(CO) 5 ( 5 ) or [(OC) 5 W] 2 SbR ( 6 ). 1 or 2 reacts with MeI and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) to give R(Me)Sb−Sb(Me)R ( 7 ) or R(Me)SbH ( 8 ). 2 reacts with SbCl 3 and pyridine to form R 4 Sb 8 ( 9 ). Photochemical degradation of 9 gives cyclo-R 3 Sb 3 ( 10 ). Dehydrogenation of 1 in the presence of LiAlH 4 leads to the cis,trans isomer of R 4 Sb 4 ( 11 ), which in the presence of light forms all - trans - 11 and 10 . Decomposition of 1 in the presence of t BuONa leads to R 6 Sb 8 ( 12 ). The structures of meso - 3, d, l - 3, 4, 5, 9 ·2THF, and 12 were determined by X-ray diffraction. The deuterium derivatives of 1, 2, and 8 were synthesized and characterized spectroscopically.