The reaction of nitrous acid with 1-aryl-2-(arylsulfonyl)ethanones3a–eafforded the unexpected arenecarboxylic acids12a–e, formic acid14, and benzene/4-toluenesulfinic acid15a,bthrough oxidative cleavage reaction. 4-Chlorobenzoic acid (12a), [1,1′-biphenyl]-4-carboxylic acid (12b), 2-naphthoic acid (12c), 2-thiophenecarboxylic acid (12d), and 2-benzofurancarboxylic acid (12e) were isolated in 72%, 62%, 55%, 58%, and 62% yields, respectively. The reported mechanistic pathways proposed the production of 1-aryl-2-(phenyl/tolylsulfonyl)ethane-1,2-dione7instead of arenecarboxylic acids12. A mechanistic pathway to explain the reaction of nitrous acid with 1-aryl-2-(arylsulfonyl)ethanones3a–ewas suggested. In this pathway, the intermediate 1,2-oxazete10lost benzene/4-toluenesulfinic acid15to produce 1,2-oxazet-3-one11. Ring cleavage of the latter intermediate afforded the arenecarboxylic acids12.
硝酸与1-芳基-2-(芳基磺酰基)乙酮酮3a-e反应产生了意外的芳基羧酸12a-e、甲酸14和苯/对甲苯磺酸15a、b,通过氧化裂解反应。4-氯苯甲酸(12a)、[1,1'-联苯]-4-羧酸(12b)、2-萘甲酸(12c)、2-噻吩羧酸(12d)和2-苯并呋喃羧酸(12e)分别以72%、62%、55%、58%和62%的产率分离。报道的机理途径提出了1-芳基-2-(苯基/甲苯基磺酰基)乙烷-1,2-二酮7的产生,而不是芳基羧酸12。提出了一种解释硝酸与1-芳基-2-(芳基磺酰基)乙酮酮3a-e反应的机理途径。在这个途径中,中间体1,2-噁唑烷10失去苯/对甲苯磺酸15,产生1,2-噁唑烷-3-酮11。后者的环裂解产生了芳基羧酸12。