Synlett 2018; 29(05): 609-612
DOI: 10.1055/s-0036-1591739
letter
© Georg Thieme Verlag Stuttgart · New York

A Combined Tamaru Allylation/Olefin Cross-Metathesis Approach for the Total Syntheses of (±)-Paniculidine B, (±)-Paniculidine C, and 2-Methylcarbazole

Yi-Lun Tseng
a  Department of Applied Chemistry, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan
,
Min-Chieh Liang
a  Department of Applied Chemistry, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan
,
I-Chia Chen
b  Department of Cosmetic Applications and Management, Cardinal Tien Junior College of Healthcare and Management, New Taipei City 23143, Taiwan   Email: yenkuwu@nctu.edu.tw
,
a  Department of Applied Chemistry, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan
› Author Affiliations
We thank the Ministry of Science and Technology, Taiwan for financial support of this work (Grant Nos. 104-2113-M-009-022-MY2 and 106-2113-M-009-011-MY2).
Further Information

Publication History

Received: 07 October 2017

Accepted after revision: 18 November 2017

Publication Date:
20 December 2017 (eFirst)

Abstract

A concise approach to the total syntheses of racemic paniculidines B and C is described. The route features a combined Tamaru allylation/olefin cross-metathesis sequence for the regiocontrolled synthesis of prenylindole intermediates. In addition, we report a transformation of the prenylated indole into 2-methylcarbazole catalyzed by sulfonic acid-functionalized silica gel.

Supporting Information

 
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