Issue 5, 2018

Guiding a divergent reaction by photochemical control: bichromatic selective access to levulinates and butenolides

Abstract

Allylic and acrylic substrates may be efficiently transformed by a sequential bichromatic photochemical process into derivatives of levulinates or butenolides with high selectivity when phenanthrene is used as a regulator. Thus, UV-A photoinduced cross-metathesis (CM) couples the acrylic and allylic counterparts and subsequent UV-C irradiation initiates EZ isomerization of the carbon–carbon double bond, followed by one of two competing processes; namely, cyclization by transesterification or a 1,5-H shift and tautomerization. Quantum chemical calculations demonstrate that intermediates are strongly blue-shifted for the cyclization while red-shifted for the 1,5-H shift reaction. Hence, delaying the double bond migration by employing UV-C absorbing phenanthrene, results in a selective novel divergent all-photochemical pathway for the synthesis of fundamental structural motifs of ubiquitous natural products.

Graphical abstract: Guiding a divergent reaction by photochemical control: bichromatic selective access to levulinates and butenolides

Supplementary files

Article information

Article type
Edge Article
Submitted
29 Nov 2017
Accepted
18 Dec 2017
First published
18 Dec 2017
This article is Open Access

All publication charges for this article have been paid for by the Royal Society of Chemistry
Creative Commons BY license

Chem. Sci., 2018,9, 1368-1374

Guiding a divergent reaction by photochemical control: bichromatic selective access to levulinates and butenolides

Revannath L. Sutar, S. Sen, O. Eivgi, G. Segalovich, I. Schapiro, O. Reany and N. G. Lemcoff, Chem. Sci., 2018, 9, 1368 DOI: 10.1039/C7SC05094A

This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements