α-Iodination of Some Aliphatic Acids. Substituent Effect and Optimum Conditions

Article abstract of DOI:10.1021/jo01302a016

The chlorosulfonic acid promoted α-iodination of some aliphatic acids in 1,2-dichloroethane has been studied.In contrast to the bromination, the effect of substituents on the rate shows not only a polar effect but also a steric effect in view of Taft's equation: , where ρ_? = -1.20 and δ = 1.55 at 80 deg C.The transition state is discussed, which involves the electrophilic addition of I2 to a ketene intermediate.Aliphatic acids with less steric hindrance at the α-position, except acetic acid, are α-iodinated in good yields (ca. 80-100percent).The optimumconditions for α-iodination of long-chain aliphatic acids with caprylic acid as a model substrate are described.

Full text of DOI:10.1021/jo01302a016

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Evaluation Only. Created with Aspose.PDF. Copyright 2002-2021 Aspose Pty Ltd.

Evaluation Only. Created with Aspose.PDF. Copyright 2002-2021 Aspose Pty Ltd.

Evaluation Only. Created with Aspose.PDF. Copyright 2002-2021 Aspose Pty Ltd.