反应详情

A heterogenous mixture of methanol (2 ml), CH2Cl2 (3 ml), 4-chloro-3-methoxybenzaldehyde (2 g, 11.7 mmol; prepared essentially as described by R. M. Riggs et al., J. Med. Chem., 30 1887, 1987.), trimethyl orthoformate (1.7 ml, 15.5 mmol) and a large crystal of p-toluenesulfonic acid was stirred at room temperature for one hour. Additional MeOH (1 ml) and a crystal of p-toluenesulfonic acid were added and the solution was warmed until homogenous. Upon completion of the reaction, the solution was stirred 5 min with excess solid NaHCO3 and rotory evaporated to remove solvents. The paste was dissolved in 40 ml EtOAC, partitioned against dilute NaHCO3 solution, and evaporated to yield a light brown oil. The reaction was repeated with another 2 g of 4-chloro-3-methoxybenzaldehyde and both product oils were combined to give 4.37 g (86%) of dimethyl acetal 3.

1. customprepared essentially
2. temperaturethe solution was warmed until homogenous
3. customUpon completion of the reaction
4. customevaporated
5. customto remove solvents
6. dissolutionThe paste was dissolved in 40 ml EtOAC
7. custompartitioned against dilute NaHCO3 solution
8. customevaporated
9. customto yield a light brown oil