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Simple Synthesis of Amides and Weinreb Amides via Use of PPh3 or Polymer-Supported PPh3 and Iodine.

ABSTRACT: The combination of PPh3/I2 has been shown to be effective for conversion of a range of carboxylic acids to 2°, 3°, and Weinreb amides. Simplification of the procedure was possible with the use of polymer-supported PPh3/I2. Weinreb amides produced via the use of polymer-supported PPh3 could be filtered through a short silica gel plug and used in further transformations. Thus, use of polymer-supported PPh3 offers potential applicability to diversity-oriented reactions. Formal total syntheses of apocynin and pratosine, as well as syntheses of anhydrolychorinone and hippadine, have been achieved via the use of this amide-forming method. An attempt has been made to gain insight into this reaction.

SUBMITTER: Kumar A

PROVIDER: S-EPMC3818920 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature

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Simple Synthesis of Amides and Weinreb Amides via Use of PPh3 or Polymer-Supported PPh3 and Iodine.

Kumar Amit A Akula Hari Kiran HK Lakshman Mahesh K MK

European journal of organic chemistry 20100501 14

The combination of PPh3/I2 has been shown to be effective for conversion of a range of carboxylic acids to 2°, 3°, and Weinreb amides. Simplification of the procedure was possible with the use of polymer-supported PPh3/I2. Weinreb amides produced via the use of polymer-supported PPh3 could be filtered through a short silica gel plug and used in further transformations. Thus, use of polymer-supported PPh3 offers potential applicabi ...[more]

PMID: 24223494

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