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A Mild and General Larock Indolization Protocol for the Preparation of Unnatural Tryptophans

Chuang, Kangway V. and Kieffer, Madeleine E. and Reisman, Sarah E. (2016) A Mild and General Larock Indolization Protocol for the Preparation of Unnatural Tryptophans. Organic Letters, 18 (18). pp. 4750-4753. ISSN 1523-7060. PMCID PMC5505074. doi:10.1021/acs.orglett.6b02477.

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A mild and general protocol for the Pd(0)-catalyzed heteroannulation of o-bromoanilines and alkynes is described. Application of a Pd(0)/P(^tBu)_3 catalyst system enables the efficient coupling of o-bromoanilines at 60 °C, mitigating deleterious side reactions and enabling access to a broad range of useful unnatural tryptophans. The utility of this new protocol is demonstrated in the highly convergent total synthesis of the bisindole natural product (−)-aspergilazine A.

Item Type:Article
Related URLs:
URLURL TypeDescription Information CentralArticle
Chuang, Kangway V.0000-0002-0652-8071
Reisman, Sarah E.0000-0001-8244-9300
Additional Information:© 2016 American Chemical Society. Received: August 18, 2016; Publication Date (Web): September 6, 2016. We thank Dr. Scott Virgil of Caltech for helpful discussions, the Caltech Center for Catalysis and Chemical Synthesis for access to screening facilities and analytical equipment, and Sigma–Aldrich for a kind donation of chemicals. We gratefully acknowledge Jordan Beck and Lauren Chapman of Caltech for their assistance in the preparation of this manuscript. Fellowship support was provided by the National Science Foundation (Graduate Research Fellowship to M.E.K. and K.V.C., Grant No. DGE-1144469). S.E.R. is an American Cancer Society Research Scholar and a Heritage Medical Research Foundation investigator. Financial support from the NIH (NIGMS RGM097582A) and the donors of the ACS Petroleum Research Foundation is gratefully acknowledged. The authors declare no competing financial interest.
Group:Heritage Medical Research Institute
Funding AgencyGrant Number
NSF Graduate Research FellowshipDGE-1144469
American Cancer SocietyUNSPECIFIED
Heritage Medical Research InstituteUNSPECIFIED
American Chemical Society Petroleum Research FundUNSPECIFIED
Issue or Number:18
PubMed Central ID:PMC5505074
Record Number:CaltechAUTHORS:20160912-094332366
Persistent URL:
Official Citation:A Mild and General Larock Indolization Protocol for the Preparation of Unnatural Tryptophans Kangway V. Chuang, Madeleine E. Kieffer, and Sarah E. Reisman Organic Letters 2016 18 (18), 4750-4753 DOI: 10.1021/acs.orglett.6b02477
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:70275
Deposited By: Tony Diaz
Deposited On:12 Sep 2016 18:37
Last Modified:19 Apr 2022 17:12

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