S-Thioacyldithiophosphates proved to be excellent thioacylating agents. They are easily available from carboxylic acids. Due to their low reactivity towards oxygen nucleophiles and high reactivity towards nitrogen ones they found application in the synthesis of thiohydroxamic acids directly from hydroxylamines without protection on the hydroxy group. However, in cases of steric hindrance O-thioacyl hydroxylamines are formed and can be isolated with high yield.
S-
硫代酰基
二硫代磷酸盐被证明是非常优秀的
硫代酰化试剂,它们可从
羧酸中容易地获得。由于它们对氧亲核试剂的反应性低,但对氮亲核试剂的反应性高,因此它们在直接从
羟胺合成
硫代羟
肟酸时无需对羟基进行保护。然而,在存在立体阻碍的情况下会形成O-
硫代酰基
羟胺,并且可以高产率地分离出来。