1,3-Dihydro-5-(2-chlorophenyl)-2H-1,4-benzodiozepin-2-one synthesis

Yield:3022-68-2 79%

Reaction Conditions:

with potassium fluoride;palladium diacetate in tetrahydrofuran;lithium hydroxide monohydrate at 20; for 6 h;Inert atmosphere;

Steps:

5-(2-Chlorophenyl)-1,3-dihydro-2H-benzo[e][1,4]diazepin-2-one (3)

7-Bromo-5-(2-chlorophenyl)-1,3-dihydro-2H-benzo[e][1,4]diazepin-2-one (1) (0.8 g, 2.28 mmol) was dissolvedin THF (10 mL) under argon and then Pd(OAc)2 (0.051 g, 0.114 mmol), and an aq potassium fluoride ( 0.264 g,4.56 mmol in 2 mL water) solution was added under a positive flow of argon and this was followed by dropwiseaddition of PMHS (0.14 mL, 2.39 mmol). The reaction mixture, which resulted, was stirred the appropriate time(see Table 2) at rt and the flask was opened to the air to form more black palladium oxide and stirred withalumina, and then filtered through celite. The aq layer was extracted with ethyl acetate (3x10 mL); and thecombined organic layer was washed with aq 10% sodium chloride solution (2x10 mL). It was then dried (Na2SO4)and concentrated under reduced pressure. The residue was purified by silica gelchromatography using EtOAc:hexane (40:60). The desired fractions were collected, evaporated and dried under vacuum to obtain a whitepowder 3 (0.51 g, 75% yield). 1H NMR (500 MHz, CDCl3) δ 9.39 (s, 1H), 7.55 (ddd, J 7.6, 4.7, 2.3 Hz, 1H), 7.49(ddd, J 8.7, 6.1, 2.8 Hz, 1H), 7.41 - 7.37 (m, 3H), 7.19 (d, J 8.3 Hz, 1H), 7.11 (ddd, 2H), 4.42 (s, 2H).13C NMR (126MHz, CDCl3) δ 171.57 (s), 170.57 (s), 139.10 (s), 137.96 (s), 133.27 (s), 131.85 (s), 131.03 (s), 130.63 (s), 130.03(s), 129.90 (s), 127.91 (s), 126.84 (s), 123.85 (s), 121.04 (s), 56.59 (s). HRMS (ESI/ITTOF) m/z: [M + H]+Calcd forC15H11N2OCl 271.0633; found 271.0608.

References:

Chan, John D.;Cook, James M.;Golani, Lalit K.;Mian, Md Yeunus;Mirza, Shama P.;Mondal, Prithu;Pandey, Kamal P.;Phani Babu Tiruveedhula, V. V. N.;Rajaratnam, Vilashini;Rashid, Farjana;Rezvanian, Sepideh;Sharmin, Dishary;Witkin, Jeffrey M. [Arkivoc,2022,vol. 2021,# 5,p. 171 - 188]