Cu(ii)-tBu-PHOX catalyzed enantioselective malonate addition onto 3-hydroxy 2-oxindoles: application in the synthesis of dimeric pyrroloindoline alkaloidsElectronic supplementary information (ESI) available: Experimental procedures, additional reaction optimization, and spectroscopic data for all new compounds. See DOI: 10.1039/c8cc04338h

An efficient Cu( ii )-PHOX-catalyzed malonate addition onto 3-hydroxy 3-indolyl-2-oxindoles is envisioned to afford excellent enantioselectivities (up to >99% ee) in high chemical yields. Detailed characterization techniques including X-ray, NMR, CV and EPR experiments suggest that a Cu( ii )-com...

Full description

Saved in:
Bibliographic Details
Main Authors: Babu, K. Naresh, Kinthada, Lakshmana K, Pratim Das, Partha, Bisai, Alakesh
Format: Article
Language:English
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:An efficient Cu( ii )-PHOX-catalyzed malonate addition onto 3-hydroxy 3-indolyl-2-oxindoles is envisioned to afford excellent enantioselectivities (up to >99% ee) in high chemical yields. Detailed characterization techniques including X-ray, NMR, CV and EPR experiments suggest that a Cu( ii )-complex is involved as an active species in this process. Applying this strategy, an advanced intermediate of cyclotryptamine alkaloids has been synthesized in few steps for a general approach to bis-cyclotryptamine alkaloids. Cu( ii )-PHOX-catalyzed malonate addition onto 3-hydroxy 3-indolyl-2-oxindoles afforded products in >99% ee. A Cu( ii )-species has been identified as an active species based on detailed X-ray, NMR, CV and EPR experiments.
ISSN:1359-7345
1364-548X
DOI:10.1039/c8cc04338h