Synthesis 2014; 46(16): 2220-2224
DOI: 10.1055/s-0033-1339129
paper
© Georg Thieme Verlag Stuttgart · New York

Synthesis of 3-exo-Aroylhexahydroindoles via Sequential Gold(I)-Catalyzed Claisen-Type Rearrangement–Epimerization Reactions of cis-4-[N-Tosyl-N-(3-arylprop-2-ynyl)amino]cyclohex-2-en-1-ols

Chia-Jung Liang
Department of Chemistry, National Taiwan Normal University, 88 Ding-Jou Road, Section 4, Taipei 11677, Taiwan, R. O. C.   Fax: +886(2)29324249   Email: cheyeh@ntnu.edu.tw
,
Xuan-Yi Jiang
Department of Chemistry, National Taiwan Normal University, 88 Ding-Jou Road, Section 4, Taipei 11677, Taiwan, R. O. C.   Fax: +886(2)29324249   Email: cheyeh@ntnu.edu.tw
,
Ming-Chang P. Yeh*
Department of Chemistry, National Taiwan Normal University, 88 Ding-Jou Road, Section 4, Taipei 11677, Taiwan, R. O. C.   Fax: +886(2)29324249   Email: cheyeh@ntnu.edu.tw
› Author Affiliations
Further Information

Publication History

Received: 18 March 2014

Accepted after revision: 22 April 2014

Publication Date:
02 June 2014 (online)


Abstract

A two-step process for the synthesis of 3-exo-aroylhexahydroindoles is described. cis-4-[N-Tosyl-N-(3-arylprop-2-ynyl)amino]cyclohex-2-en-1-ols were cycloisomerized with a catalytic amount of chloro(triphenylphosphine)gold(I)/silver(I) hexafluoroantimonate (AuPPh3Cl/AgSbF6); subsequent base treatment of the crude mixture provided 3-exo-aroylhexahydroindoles in good yields and complete stereoselectivity. A key step involving a 9-endo-dig attack of the hydroxyl group onto the gold-activated alkyne is proposed. The resulting allyl vinyl ether intermediate underwent a gold-assisted [3,3]-sigmatropic rearrangement to form 3-exo-3-aroylhexahydroindole derivatives.

Supporting Information