1,1,3,3-Tetramethylguanidine → Methyl (2Z)-2-{[(benzyloxy)carbonyl]amino}-3-(1-methylcyclohexyl)acrylate

Participants

Reaction Conditions

Reaction Steps

1-Methylcyclohexanecarbaldehyde (2.66 g, 21.08 mmol) and methyl {[(benzyloxy)carbonyl]amino}(dimethoxyphosphoryl)acetate (6.63 g, 20.02 mmol, 0.95 equivalent) are dissolved in 75 ml of tetrahydrofuran and cooled to −78° C. At −78° C., N,N,N′,N′-tetramethylguanidine (27.92 g, 0.24 mol, 11.5 equivalents) is added dropwise and then stirred at −78° C. for 15 min and subsequently at room temperature for 4 days. The mixture is then extracted by shaking with ethyl acetate (twice 100 ml) and water, and the combined organic phases are washed with saturated sodium chloride solution and dried over sodium sulphate. After concentration, the crude product is chromatographed (Biotage 40M, cyclohexane/ethyl acetate 6/1, 27.5 ml/min). 0.91 g (13% of theory) of the title compound is obtained.

Provenance & Evidence