Syntheses, Structures and Reactivity of New Intramolecularly Coordinated Tin Alkoxides Based on an Enantiopure Ephedrine Derivative

The syntheses of the tin compounds [LSn]2 (2), spiro‐L2Sn (3), [LSnW(CO)5]2 (4), [LSnBr2]2 (5), spiro‐L2Sn·SnBr4 (6) and LSn[OC(O)Ph]2 (8), where L = MeN(CH2CMe2O)[(S)‐CH(Me)‐(R)‐CH(Ph)O], and (Ph4P)2SnBr6 (7) are reported. The compounds were characterized by elemental analysis, multinuclear NMR spectroscopy including 119Sn cross polarisation–magic angle spinning NMR (CP–MAS) (2, 3–6), electrospray ionization mass spectrometry (2–4) and single crystal X‐ray diffraction analysis (2, 2·C7H8, 3a, 3b, 4·C7H8, 5, 6·C7H8, 7). Bromide anions catalyze the rearrangement of the bromido‐substituted tin ephedrine‐based alkoxide derivative 5 to give the unprecedented tin tetrabromide coordinated spiro‐type complex 6.