Role of Auxiliary Donors in Tuning the Selectivity of C-H Activation in Arylazonaphthalenes by Palladium(II) : Isolation and Photoisomerization of Isomeric Cyclopalladates

Abstract

Selective activation of C2(naphthyl)-H and C8(naphthyl)-H bonds in a group of substrates having a diazene function as primary donor along with thioether or sulfinyl groups as auxiliary donors has been achieved by palladium(n) at room temperature. The selectivity of C(naphthyl)-H activation in the diazene substrates has been shown to be controlled by the presence of acidic or basic additives. At room temperature, regiospecific C2(naphthyi)-H has been achieved in presence of Et3N, leading to the formation of ortAo-palladate. On the other hand, regiospecific activation of C8(naphthyl)-H resulted in presence of acetic acid affording peri-palladate. The solid-state structures of the representative cyclopalladates have been determined by single crystal X-ray diffraction method. Both the ortAo-palladates and pen-palladates contain five-membered carbopalladacycles [C,N], whereas the [N,S] chelate rings are five-membered in the ortho-isomers and six-membered in peri-isomers. The photochemical transformation of the peri-palladates into the ortAo-palladates i.e. C8(naphthyl)-Pd → C2(naphthyl)-Pd has been achieved.

Department(s)

Chemistry

Keywords and Phrases

C-H activation; Cyclopallation; Isomerism; Palladium

International Standard Serial Number (ISSN)

0019-4522

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2024 Elsevier, All rights reserved.

Publication Date

01 Dec 2015

This document is currently not available here.

Share

 
COinS