LITHIUM DERIVATIVES OF 5-METHYL-5,10-DIHYDROINDENO[1,2-b] INDOLE AND 1,3,5-TRIMETHYL-6H- DIHYDROINDENO[2,1-b] INDOLE. SYNTHESIS AND MOLECULAR STRUCTURE

The reaction of 1,3-dimethyl-5,6-dihydroindeno[2,1-b]indole with methyl iodide in the presence of cetyltrimethylammonium bromide yielded 1,3,5-trimethyl-6H-indeno[2,1-b]indole (L H). The molecular structure of the compound was confirmed by X-ray diffraction. 1,3,5-Trimethyl-6H-indeno[2,1-b]indole (L H) and 5-methyl-5,10-indeno[1,2-b]indole (L H) are metallated with n-butyl lithium in diethyl ether at 0°C to form the corresponding lithium derivatives L Li(EtO) (1) and L Li(EtO) (2). According to X-ray diffraction data, lithium complex 2 has a monomeric structure, with two crystallographically independent molecules of the complex located in the independent region of the crystal cell. In molecule 2b, the lithium cation is coordinated by the five-membered ligand cycle by the η-type, and in molecule 2a, by the η-type.