THE PHENOMENON OF CONGLOMERATE CRYSTALLIZATION .24. SPONTANEOUS RESOLUTION IN COORDINATION-COMPOUNDS - CLASSICAL AND SPONTANEOUS RESOLUTION OF THE [CO(EN)2(NH3)BR]2+ CATION - CRYSTAL-STRUCTURES AND ABSOLUTE-CONFIGURATIONS OF RESOLVED (+)589-[CIS-LAMBDA(DELTA-LAMBDA)-CO(EN)2(NH3)BR]S4O6 (I) AND OF CONGLOMERATE CRYSTALS OF [CIS-LAMBDA-DELTA-LAMBDA)-CO(EN)2(NH3)BR]S4O6 (II)

Compound I, BrCoS4O6N5C4H19, crystallizes in the monoclinic space group P2(1) with cell constants a = 7.971(3) A, b = 9.610(4) angstrom, c = 10.953(4) angstrom, and beta = 103.90(5)-degrees; V = 814.43 angstrom3 and d(MW = 500.32, z = 2) = 2.040 g cm-3. The structure factors were corrected for absorption: mu = 40.036 cm-1 using psi-scan curves. The absolute configuration of the (+)589 enantiomorph was determined from refinement of the original and inverted coordinates, and the correct absolute configuration is (+)589-[cis-LAMBDA(deltalambda)-Co(en)2(NH3)Br]2+. The most interesting aspect of the crystallographic study of I is the nature of the interaction between the cation and anion, which are hydrogen-bonded such that one oxygen of -SO3 binds one of the hydrogens of the -NH3 ligand, while a second oxygen is attached to a hydrogen on an -NH2 Of an adjacent en ligand. This is precisely the interaction mode in (+)589-[cis-LAMBDA(deltalambda)-Co(en)2(NH3)Cl] (d-3-bromocamphorsulfonate)2.H2O, the cation of which is known to be very efficiently resolved by bromocamphorsulfonate. Finally, the S4O62- anion is itself intrinsically chiral (torsional angle +90.5-degrees); its absolute configuration is coupled with that of the chiral [cis-Co(en)2(NH3)Cl]2+ cation, with which it crystallizes. Crystallization of a racemic mixture of [cis-Co(en)2(NH3)Br]S4O6 II produces a conglomerate crystallizing in the same space group and with the same cell constants as those found for I.