On the preparation of azepinones

Tetrahedron Letters

Volumn 51, Issue 40, 2010, Pages 5325-5327

  Dubinina, Galyna G ^a   Yoshida, Wesley Y ^a   Chain, William J ^a,b  

^a UNIVERSITY OF HAWAII   (United States)

^b UNIVERSITY OF HAWAII CANCER CENTER   (United States)

Author keywords

Azepinone; Cycloaddition; Diels Alder; Isomerization; Ring expansion; Synthesis

Indexed keywords

1H AZEPIN 5(2H) ONE DERIVATIVE; 1H AZEPIN 5(4H) ONE; ESTER; KETONE DERIVATIVE; UNCLASSIFIED DRUG;

ARTICLE; DIELS ALDER REACTION; ISOMERIZATION;

ALNUS;

EID: 77956344619     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.tetlet.2010.08.003     Document Type: Article

References (19)

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11. The thermal electrocyclic ring closure of vinyl azides to azirines is often accompanied by dimerization to give pyrroles, polymerization, and other unproductive decomposition. Generating the azirine quickly at high temperature and high dilution minimizes these issues and provides material sufficient for use without further purification or isolation.
12. 4-Methoxy-3-buten-2-one is present in small amounts in either commercially available or freshly prepared 1-methoxy-3- trimethylsilyloxybutadiene, and is undoubtedly produced upon treatment of our crude reaction mixtures with TBAF.
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14. Direct treatment of the cycloadducts with p-TsOH resulted in ring opening products incorporating tosylate. See Supplementary data. An analogous reaction was reported with hydrochloric acid. See Ref. 2c
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