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1.
Angew Chem Int Ed Engl ; 39(19): 3432-3434, 2000 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-11091379
2.
Acta Crystallogr B ; 55(Pt 3): 410-423, 1999 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10927384

RESUMO

The geometry of the 4,8,12-trioxa-4,8,12,12c-tetrahydrodibenzo[cd,mn]pyrene system in the cationic state was established by X-ray structural resolution of the salts formed between the cation and various anions. The geometry was found to be planar for the 4,8,12-trioxa-4,8,12,12c-tetrahydrodibenzo[cd,mn]pyrenylium and 2,6,10-tri(tert-butyl)-4,8,12-trioxa-4,8,12,12c-tetrahydrodibenzo[cd,mn]pyrenylium cations with the monovalent anions I(-), BF(4)(-), PF(6)(-), AsF(6)(-), HNO(3).NO(3)(-) and CF(3)SO(3)(-), and the divalent anions S(2)O(6)(2-) and Mo(6)Cl(14)(2-). The salts were found to crystallize in distinct space groups following a characteristic pattern. Mixed cation-anion stacking resulted in space groups with high symmetry: Pbca in three cases and R3;c in one; a temperature study of the latter was made at ten different temperatures. The formation of dimers of anions and cations resulted in lower-symmetry space groups, mainly monoclinic (P2(1)/n, P2(1)/c and C2/c), but also P1;.

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