反应详情

The same 1 L four-neck flask that was used in Example 1 was charged with 600 g of raw material containing 557 g (1.96 mol) of dimethyl 2-pentyl-3-oxo-cyclopentylmalonate produced in the same manner as in Production Example 1 and the raw material was heated to 180° C. with stirring under normal pressure. Then, the supply of water to the bottom of the reactor was started. During the supply of water, the supply rate of water was adjusted to a constant rate (6 g/h). Then, the reaction was completed for 9 hours from the start of the supply of water. During the supply of water, the content of water in the reaction solution was measured by a Karl Fischer's coulometric titration (instrument: Trace-water measuring device AQ-7, manufactured by HIRANUMA SANGYO Co., Ltd.) and as a result, the maximum water concentration in the reaction solution was 0.44% by weight. It was found that the reaction product contained 402 g (1.78 mol, yield: 90.7%) of methyl 2-pentyl-3-oxo-cyclopentylacetate and 33.5 g (0.158 mol) of 2-pentyl-3-oxo-cyclopentylacetic acid.

1. customproduced in the same manner as in Production Example 1
2. concentrationthe maximum water concentration in the reaction solution