Selective 1, 4-Addition of Arenes to 3-Chloro-3-cyclobutene-1, 2-dione under Friedel-Crafts Conditions. Synthesis and Reactivity of 4-Aryl-3-chloro-2-hydroxy-2- …
AH Schmidt, G Kircher, S Maus…
文献索引：Schmidt, Arthur H.; Kircher, Gunnar; Maus, Stephan; Bach, Heinz Journal of Organic Chemistry, 1996 , vol. 61, # 6 p. 2085 - 2094
The reaction of semisquaric chloride (7) with arenes 2 has been investigated. In the presence of 1.1 equiv of AlCl3 and in the temperature range of-15° C to rt the arenes 2a-q afford the 4-aryl-3-chloro-2-hydroxy-2-cyclobuten-1-ones (chloroenols) 8a-q in good yield. By contrast, 7 reacts with 1, 4-dimethoxybenzene (2l) in boiling CH2Cl2 to give a mixture of (2, 5-dimethoxyphenyl) cyclobutenedione (9a)(27% yield) and bis (2, 5-dimethoxyphenyl) ...
