Yield:-

Reaction Conditions:

with n-butyllithium in tetrahydrofuran;hexane;

Steps:

V 2,3-Dichloro-6-fluorobenzaldehyde

EXAMPLE V 2,3-Dichloro-6-fluorobenzaldehyde Butyl lithium (48 ml of 1.6M in hexane, 52.3 mmoles) was added with stirring over 1.5 hours under nitrogen to a solution of 1,2-dichloro-4-fluorobenzene (7.85 g, 47.6 mmoles) in dry tetrahydrofuran (120 ml) at -68°. The solution wa stirred at -68° for 2 hours and then N-methyl-N-phenylformamide (6.48 ml) in dry tetrahydrofuran (15 ml) was added over 1.5 hours. After a further 1.5 hours at -68°, the reaction mixture was poured into 10% aqueous sulphuric acid and ether. The ethereal layer was separated, washed with brine, dried (Na₂ SO₄) and evaporated to give the desired aldehyde (8 g). M⁺ 196/194/192, nmr (CDCl₃)δ10.5 (s,H).

References:

US4607041,1986,A