Annulation strategies for the synthesis of azulenes and polycyclic nitrogen heterocycles

Highly convergent annulation strategies have been developed for the synthesis of azulenes and polycyclic nitrogen heterocycles. Specifically, substituted azulenes have been synthesized via a ring expansion-annulation strategy based on n-halo diazo ketones. The method employs the use of readily available benzenoid starting materials and achieves the synthesis of azulenes substituted on both the five- and seven-membered rings regioselectively. The synthetic utility of the ring expansion annulation products, in particular azulenyl halides and triflates, has been demonstrated by their successful application in transition metal-mediated carbon-carbon bond forming reactions. These reactions have been used to further functionalize the five- and seven-membered rings and also in the synthesis of oligoazulenes and azulenylamino acid derivatives. In addition, polycyclic nitrogen heterocycles have been synthesized via a tandem ring forming strategy. The strategy employs a novel benzannulation reaction of substituted cyclobutenones with ynamides, which are synthesized via the strategy for the N-alkynylation of amides strategy developed in the Danheiser laboratory. The products of these benzannulation reactions, highly-substituted anilines, then participate in ring closing metathesis reactions to form various nitrogen heterocycles. In particular dihydroquinolines, hydrobenzoazepines, and hydrobenzoazocines were synthesized via this tandem ynamide benzannulation ring closing metathesis strategy.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Chemistry.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2004

Author dc:creator

• Crombie, Aimee Lynn, 1977-

Advisor dc:contributor.advisor

• Rick L. Danheiser.

• Chemistry.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/31113

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/31113