6-broMo-3-(4-broMophenyl)-3,4-dihydroquinazoline synthesis

Yield:65331-45-5 57%

Reaction Conditions:

with trifluoroacetic acid in benzene at 80 - 85; for 1.5 h;

Steps:

3-(m-Nitrophenyl)-5-nitro-3,4-dihydroqunazoline(3a)

General procedure: a. A mixture of 4.14 g (30 mmol) of m-nitroaniline 1a, 8 mL of benzene, 4.44 g (60 mmol) of 1,3-dioxolane 2, and 8 mL of trifluoroacetic acid was heated for 1.5 h at 80-85°C. After cooling the mixture was diluted with water. The precipitate was separated,washed twice with water, neutralized with 10% NH4OH solution to pH 8, and dried. Yield 2.3 g (52%),yellow crystals, mp 198-200°C (benzene). 1 NMRspectrum (CDCl3), δ, ppm: 5.35 s (2H, CH2), 7.35-7.69 m (5Ar), 7.93 d (1, 6, J = 8.4 Hz), 8.09-8.12 m (2, 4', =N). Mass spectrum, m/z (Irel,%): 298 (10.36) [M]+.

References:

Yunnikova;Esenbaeva [Russian Journal of General Chemistry,2016,vol. 86,# 7,p. 1769 - 1771][Zh. Obshch. Khim.,2016,vol. 86,# 7,p. 1223 - 1225,3]