Home
Resources
Publications
Copper-Catalyzed One-Pot Cross-Dehydrogenative Thienannulation: Chemoselective Access to Naphtho[2,1-b]thiophene-4,5-diones and Subsequent Transformation to Benzo[a]thieno[3,2-c]phenazines

Copper-Catalyzed One-Pot Cross-Dehydrogenative Thienannulation: Chemoselective Access to Naphtho[2,1-b]thiophene-4,5-diones and Subsequent Transformation to Benzo[a]thieno[3,2-c]phenazines

Gaurav Shukla, Abhijeet Srivastava, Dhananjay Yadav, Maya Shankar Singh

J Org Chem. 2018 Feb 16;83(4):2173-2181.

PMID: 29345936

Abstract:

A facile, cost-effective, and highly efficient copper-catalyzed, TEMPO-mediated straightforward synthesis of 2,3-disubstituted naphtho[2,1-b]thiophene-4,5-diones has been achieved via cross-dehydrogenative thienannulation. The reaction proceeded via in situ generated naphthalene-1,2-diones by dearomatization of β-naphthols, followed by oxidative heteroannulation with α-enolic dithioesters chemoselectively in an open flask. Further, the naphtho[2,1-b]thiophene-4,5-diones undergo l-proline-catalyzed cross-dehydrative coupling with ortho-phenylenediamine enabling pentacyclic benzo[a]thieno[3,2-c]phenazines in good yields under solvent-free conditions. A mechanistic rationale for this cascade reaction sequence is well supported by the control experiments.

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
AP243469	Benzo[b]naphtho[2,3-d]thiophene		243-46-9	Price
AP551907643	Thiophene-4		551907-64-3	Price

As a specialist in analytical chemical Products, Alfa Chemistry offers consumers a wealth of raw materials and a full range of technologies and services.

QUICK LINKS

HEADQUARTERS

Tel:

Fax:

Email: