25731-32-2Relevant academic research and scientific papers
Synthesis and Structure Determinations of Complexes Containing a Five-Membered Lactam Structure Based on Organohydrazido(2-) Ligands
Seino, Hidetake,Ishii, Youichi,Hidai, Masanobu
, p. 161 - 171 (1997)
Acid-catalyzed reactions of the hydrazido(2-) complexes cis,mer-[WX2(NNH2)(PMe2Ph)3] (X = Cl, Br) with phthalaldehyde gave the (phthalimidin-2-yl)imido complexes cis,mer-[WX2(NNCH2CH2C6H 4CO)(PMe2Ph)3], via the condensation of the terminal NH2 group with one of the formyl groups and the following cyclization to form a phthalimidine ring. Crystal structure of the chloro complex 3a was unambiguously determined by X-ray analysis. Reaction of 3a with HBr liberated the (phthalimidin-2-yl)imido ligand as 2-aminophthalimidine in moderate yield, while treatment of 3a with KOH in THF selectively cleaved the N-N bond to give phthalimidine. A similar condensation of the hydrazido(2-) complex trans-[WF(NNH2)(dppe)2]+ (8a+; dppe = Ph2PCH2CH2PPh2) with phthalaldehyde resulted in the formation of the diazoalkane complex trans-[WF(NN=CHC6H4CHO)(dppe)2]+. However, further treatment of the latter complex with AlCl3 afforded the corresponding (phthalimidin-2-yl)imido complex trans-[WF(NNCH2C6H4CO)(dppe)2] +. When 8a+ and its molybdenum analogue were reacted with 2,5-dimethoxy-2,5-dihydrofuran in the presence of a catalytic amount of acid, trans-[MF(NNCH=:CHCH2CO)(dppe)2]+ (11+; M = Mo, W) was formed as the kinetic product, which gradually isomerized to the thermodynamically more stable compound trans-[MF(NNCH2CH=CHCO)(dppe)2]+ (12+). Both 11+ and 12+ (M = W) were crystallographically characterized, and the mechanism for the isomerization of 11+ to 12+ was proposed based on the results of the 1H NMR measurements.
