A solution of 1,3-dibromo-5-chlorobenzene (1 mmol) in ethyl ether was cooled to ?78° and n-butyllithium in hexane (1.1 mmol) was added over 2 min.The reaction mixture was stirred at ?78° for an additional 10 min, and then 5-chloro-N,2-dimethoxy-N-methylbenzamide (1 mmol) was added in small portions over 4 min. The reaction mixture was stirred at ?78° for 1.25 h and then allowed to warm to r.t. and stirred for 14 h (97%).
