Oxidative ring expansion of 3-hydroxy-3-phenacyloxindoles using phenyliodine diacetate and molecular iodine: Synthesis of 2-hydroxy-2-aryl/alkyl-2,3-dihydroquinolin-4(1H)-ones

Oxidation of tertiary alcohol of the type 3-hydroxy-3-phenacyloxindoles using the combination of phenyliodine diacetate and molecular iodine in methanol results in oxidative cleavage of C2-C3 bond to form isocyanate as an intermediate with its subsequent trapping by methanol to form ortho-carbamates of 1,3-diaryl carbonyl compounds which further undergoes concurrent cyclization to furnish 2-hydroxy-2-aryl/alkyl-2,3-dihydroquinolin-4(1H)-ones derivatives in good yields. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

The oxidation of tertiary alcohols of the type 3-hydroxy-3-phenacyloxindoles using phenyliodine diacetate and molecular iodine in methanol results in the formation of 2-hydroxy-2-aryl/alkyl-2,3-dihydroquinolin-4(1H)-one derivatives in good yields.