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Abstract A dual‐concurrent atom transfer radical polymerization/reversible addition‐fragmentation chain‐transfer (ATRP/RAFT) system is used to control a radical polymerization by electrochemical reduction of small amount of copper complexes in the presence of a chain transfer agent (CTA). Electrochemical ATRP conditions provide a continuous supply of radicals, while the CTA aids the control over molecular weight and dispersity of poly(n‐butyl acrylate), even in the presence of low ppm amounts of catalyst. The polymerization could be turned “on” and “off” by shifting electrolysis potential. With as low as 10 ppm of Cu catalyst, addition of only 2% CTA (with respect to the ATRP initiator) improves control by decreasing dispersity fromÐ= 1.41 toÐ= 1.25.
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Metallic Impurities in Electrolysis: Catalytic Effect of Pb Traces in Reductive Amination and Acetone Reduction
Abstract The electrochemical hydrogenation (e‐hydrogenation) of unsaturated compounds like imines or carbonyls presents a benign reduction method. It enables direct use of electrons as reducing agent, water as proton source, while bypassing the need for elevated temperatures or pressures. In this contribution, we discuss the active species in electrocatalytic reductive amination with the transformation of acetone and methylamine as model reaction. Surprisingly, lead impurities in the ppm‐range proved to possess a significant effect in e‐hydrogenation. Accordingly, the influence of applied potential and cathode material in presence of 1 ppm Pb was investigated. Finally, we transferred the insights to the reduction of acetone manifesting comparable observations as for imine reduction. The results suggest that previous studies on electrochemical reduction in the presence of lead electrodes should be re‐evaluated.
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- Award ID(s):
- 2140374
- PAR ID:
- 10558560
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 63
- Issue:
- 49
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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