| 摘要 |
<p>A method for the preparation of 5cyanophthalide comprising treatment of a compound of formula (IV) wherein X is O or S; R1R2 are each independently selected from hydrogen and C16alkyl, or R1 and R2 together form a C25alkylene chain thereby forming a spiroring; R3 is selected from hydrogen and C16alkyl, R4 is selected from hydrogen, C16alkyl, a carboxy group or a precursor group therefore, or R3 and R4 together form a C25alkylene chain thereby forming a spiroring; with a dehydration agent or alternatively where X is S, thermally cleavage of the thiazoline ring or treatment with a radical initiator, such as peroxide or with light, to form 5cyanophthalide, which is an important intermediate used in the preparation of the antidepressant drug citalopram.</p> |
