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Synthesis of 2-Azaadamantan-6-one: A Missing Isomer.

ABSTRACT: 2-Azaadamantan-6-one and its Boc and ethylene ketal derivatives were synthesized from 9-oxo endo-bicyclo[3.3.1]non-6-ene-3-carboxylic acid. Similarly, the Cbz, Boc, and ethylene ketal derivatives of 2-azaadamantan-4-one were synthesized from endo-bicyclo[3.3.1]non-6-ene-3-carboxylic acid. Key steps were Curtius rearrangements to form benzyl carbamates, followed by spontaneous intramolecular attack of the carbamate nitrogen on transient bromonium ion or epoxide intermediates to effect ring closure to azaadamantane intermediates. The reaction sequence leading to 2-azaadamantan-6-one is consistent with the formation of a transient tetracyclic keto aziridine intermediate.

SUBMITTER: Wu J

PROVIDER: S-EPMC6166225 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Synthesis of 2-Azaadamantan-6-one: A Missing Isomer.

Wu Jianbo J Leas Derek A DA Dong Yuxiang Y Wang Xiaofang X Ezell Edward L EL Stack Douglas E DE Vennerstrom Jonathan L JL

ACS omega 20180918 9

2-Azaadamantan-6-one and its Boc and ethylene ketal derivatives were synthesized from 9-oxo <i>endo</i>-bicyclo[3.3.1]non-6-ene-3-carboxylic acid. Similarly, the Cbz, Boc, and ethylene ketal derivatives of 2-azaadamantan-4-one were synthesized from <i>endo</i>-bicyclo[3.3.1]non-6-ene-3-carboxylic acid. Key steps were Curtius rearrangements to form benzyl carbamates, followed by spontaneous intramolecular attack of the carbamate nitrogen on transient bromonium ion or epoxide intermediates to effe ...[more]

PMID: 30288462

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