Coomber, CE;
Porter, MJ;
Aliev, AE;
Smith, PD;
Sheppard, TD;
(2020)
Tuning Reactivity in Pd-catalysed C(sp(3))-H Arylations via Directing Group Modifications and Solvent Selection.
Advanced Synthesis & Catalysis
10.1002/adsc.202000726.
(In press).
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Abstract
The palladium‐catalysed sp3 C−H arylation of a selection of saturated amine scaffolds was investigated using substituted picolinamide directing groups. On the bornylamine scaffold, highly selective monoarylation takes place using unsubstituted picolinamide or 3‐methylpicolinamide, whereas a double C−H arylation occurs with other substituents present, becoming a significant product with 3‐trifluoromethylpicolinamide. DFT calculations were used to help rationalise the effect of directing groups on the C−H palladation steps which were found experimentally to be irreversible. The substituted picolinamide directing groups were also examined on acyclic amine scaffolds and in many cases increased yields and selectivity could be obtained using methylpicolinamides. For a selection of other amine scaffolds, the yield of C−H arylation could be improved significantly using 3‐methylpicolinamide as the directing group and/or 3‐methylpentan‐3‐ol as the solvent.
| Type: | Article |
|---|---|
| Title: | Tuning Reactivity in Pd-catalysed C(sp(3))-H Arylations via Directing Group Modifications and Solvent Selection |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1002/adsc.202000726 |
| Publisher version: | http://dx.doi.org/10.1002/adsc.202000726 |
| Language: | English |
| Additional information: | © 2020 The Authors. Published by Wiley-VCH GmbH. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. |
| Keywords: | Palladium, C-H Activation, Density Functional Calculations, Regioselectivity, Arylation, C-H FUNCTIONALIZATION, UNACTIVATED C(SP(3))-H, INTRAMOLECULAR AMINATION, C(SP(2))-H BONDS, CYCLOPROPANES, ACTIVATION, GAMMA, PYRROLIDINES, DERIVATIVES, CYCLIZATION |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Chemistry |
| URI: | https://discovery.ucl.ac.uk/id/eprint/10111862 |
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