反应详情

A solution of diethyl methylmalonate (87 g) in absolute ethanol (100 ml) was added to a pre-formed solution of sodium (11.5 g) in ethanol (400 ml) under argon. A hot solution of p-bromobenzylbromide (125 g) in absolute alcohol (200 ml) was added rapidly with vigorous stirring, which was continued for 3 days and the solid so formed was removed by filtration. The filtrate was evaporated and the residue dissolved in ethyl acetate (1 l), washed with brine (250 ml), dried (MgSO4) and evaporated. The residual oil was distilled under vacuum to give diethyl (4-bromophenyl)methylmalonate (150.7 g) b.p. 130-133/0.03 mm Hg; 1H NMR (d6 -DMSO): 1.33 (t, 6 H), 1.4 (s, 3 H), 3.27 (s, 2 H), 4.30 (q, 4 H), 7.23 (d, 2 H), 7.6 (d, 2 H)

1. customthe solid so formed
2. customwas removed by filtration
3. customThe filtrate was evaporated
4. dissolutionthe residue dissolved in ethyl acetate (1 l)
5. washwashed with brine (250 ml)
6. dry with materialdried (MgSO4)
7. customevaporated
8. distillationThe residual oil was distilled under vacuum