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Synthesis of anionic phosphorus-containing heterocycles by intramolecular cyclizations involving N-functionalized phosphinecarboxamides.

ABSTRACT: We report that the 2-phosphaethynolate anion (PCO(-)) reacts with propargylamines in the presence of a proton source to afford novel N-derivatized phosphinecarboxamides bearing alkyne functionalities. Deprotonation of these species gives rise to novel five- and six-membered anionic heterocycles resulting from intramolecular nucleophilic attack of the resulting phosphide at the alkyne functionality (via 5-exo-dig or 6-endo-dig cyclizations, respectively). The nature of the substituents on the phosphinecarboxamide can be used to influence the outcome of these reactions. This strategy represents a unique approach to phosphorus-containing heterocylic systems that are closely related to known organic molecules with interesting bio-active properties.

SUBMITTER: Robinson TP

PROVIDER: S-EPMC4405058 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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Synthesis of anionic phosphorus-containing heterocycles by intramolecular cyclizations involving N-functionalized phosphinecarboxamides.

Robinson Thomas P TP Goicoechea Jose M JM

Chemistry (Weinheim an der Bergstrasse, Germany) 20150303 15

We report that the 2-phosphaethynolate anion (PCO(-)) reacts with propargylamines in the presence of a proton source to afford novel N-derivatized phosphinecarboxamides bearing alkyne functionalities. Deprotonation of these species gives rise to novel five- and six-membered anionic heterocycles resulting from intramolecular nucleophilic attack of the resulting phosphide at the alkyne functionality (via 5-exo-dig or 6-endo-dig cyclizations, respectively). The nature of the substituents on the pho ...[more]

PMID: 25736217

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