GOLD(I) DERIVATIVES OF BETA-CARBOLINE ALKALOIDS - MONONUCLEAR AND DINUCLEAR COMPLEXES OF HARMINE AND HARMALINE - CRYSTAL AND MOLECULAR-STRUCTURE OF (L'-H)AU(PPH3) (L'=HARMINE)

The preparation of a series of neutral (L)AuCl (1 and 2) and cationic [(L)Au(PPh3)][BF4] (3 and 4) gold(I) complexes with harmine (7-methoxy -1-methyl-9H-pyrido[3,4-b]indole), L', and harmaline dihydro-7-methoxy -1-methyl-3H-pyrido[3,4-b]indole, L'', is described. In the presence o f alkali, (PPh3)AuCl reacts with L' and L'' to give neutral gold(I) sp ecies (L-H)Au(PPh3) (5 and 6), where the deprotonated ligands are bond ed to gold via the indole nitrogen. The molecular structure of (L'-H)A u(PPh3), 5, has been solved by X-ray analysis: C31H26AuN2OP, monoclini c, space group C2/c, a = 30.608(13), b = 10.047(1), c = 21.423(12) ang strom, beta = 128.79(4)-degrees, Z = 8, Au-P = 2.232(1), Au-N = 2.031( 2) angstrom. The crystal structure was refined to R = 0.018 and R(w) = 0.023 on the basis of 3536 unique reflections with I > 3sigma(I). The complexes 5 and 6 react with [(PPh3)Au(S)][BF4], as obtained from (PP h3)AuCl and AgBF4 in methanol, to give the dinuclear cationic species [(PPh3)Au{mu(L-H)}Au(PPh3)][BF4] (7 and 8) where the deprotonated liga nds bridge two (PPh3)Au moieties through both nitrogen atoms. All the new derivatives were characterized by IR, H-1 and P-31 NMR, and FABMS spectroscopic techniques.