1807-55-2Relevant articles and documents
Friedlaender
, p. 973,989 (1902)
Synthesis, Structure, and Properties of Amino-Substituted Benzhydrylium Ions – A Link between Ordinary Carbocations and Neutral Electrophiles
Mayer, Robert J.,Hampel, Nathalie,Mayer, Peter,Ofial, Armin R.,Mayr, Herbert
supporting information, p. 412 - 421 (2018/09/14)
Optimized synthetic procedures for the straightforward access to eleven amino-substituted diarylmethylium tetrafluoroborates are described. These benzhydrylium ions cover a range of seven orders of magnitude in electrophilicity and provide a link between ordinary carbocations and neutral electrophiles. Five of these highly stabilized benzhydrylium tetrafluoroborates were characterized by single-crystal X-ray crystallography. While the experimentally determined bond lengths and angles in the solid state perfectly agree with those calculated by DFT methods for the gas phase and aqueous solution, crystal packing accounts for large differences in the twist angles of the aryl groups found in the solid state as compared to calculated structures.
Full N,N-Methylation of 4,4′-Methylenedianiline with Dimethyl Carbonate: A Feasible Access to 4,4′-Methylene bis(N,N-Dimethylaniline)
Qiu, Zegang,Wang, Kunjie,Li, Zhiqin,Li, Tao,Bai, Jinhao,Yin, Chanjuan,Ye, Xiushen,Liu, Haining
, (2018/06/20)
The full N,N-methylation of 4,4′-methylenedianiline (MDA) with dimethyl carbonate (DMC) was investigated. The yield of the major product 4,4′-methylene bis(N,N-dimethylaniline) (MBDMA) reached as high as 97% over NaY catalyst at 190°C for 6 h. The catalyst could be used for two more times with acceptable MBDMA yields higher than 90%. The main by-products were identified as three N-methylated derivatives. Surprisingly, the formation of the N-methoxycarbonylation product was extremely restrained, which could be produced in high yields of 98% on zinc acetate catalyst. Furthermore, the reaction pathway to the major product MBDMA was proposed. Finally, a feasible synthetic route of 4,4′-methylene bis(N,N-dimethylaniline) (MBDMA) was established, featuring a high yield, mild reaction conditions, and simple operations.