Azodicarboxylate-free esterification with triphenylphosphine mediated by flavin and visible light: method development and stereoselectivity control
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22310%2F18%3A43917086" target="_blank" >RIV/60461373:22310/18:43917086 - isvavai.cz</a>
Alternative codes found
RIV/60461373:22810/18:43917086
Result on the web
<a href="http://dx.doi.org/10.1039/c8ob01822g" target="_blank" >http://dx.doi.org/10.1039/c8ob01822g</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1039/c8ob01822g" target="_blank" >10.1039/c8ob01822g</a>
Alternative languages
Result language
angličtina
Original language name
Azodicarboxylate-free esterification with triphenylphosphine mediated by flavin and visible light: method development and stereoselectivity control
Original language description
Triphenylphosphine (Ph3P) activated by various electrophiles (e.g., alkyl diazocarboxylates) represents an effective mediator of esterification and other nucleophilic substitution reactions. We report herein an aza-reagent-free procedure using flavin catalyst (3-methyl riboflavin tetraacetate), triphenylphosphine, and visible light (448 nm), which allows effective esterification of aromatic and aliphatic carboxylic acids with alcohols. Mechanistic study confirmed that photoinduced electron transfer from triphenylphosphine to excited flavin with the formation of Ph3P+ is a crucial step in the catalytic cycle. This allows reactive alkoxyphosphonium species to be generated by reaction of an alcohol with Ph3P+ followed by single-electron oxidation. Unexpected stereoselectivity control by the solvent was observed, allowing switching from inversion to retention of configuration during esterification of (S)- or (R)-1-phenylethanol; for example with phenylacetic acid, the ratio shifting from 10:90 (retention:inversion) in trifluoromethylbenzene to 99.9:0.1 in acetonitrile. Our method uses nitrobenzene to regenerate the flavin photocatalyst. This new approach to flavin re-oxidation has also been successfully proved in benzyl alcohol oxidation, which is a standard process among flavin-mediated photooxidations.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10401 - Organic chemistry
Result continuities
Project
<a href="/en/project/GA16-09436S" target="_blank" >GA16-09436S: Photocatalytic and Organocatalytic Mitsunobu Reaction Mediated by Flavin derivatives and Visible Light</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2018
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Organic and Biomolecular Chemistry
ISSN
1477-0520
e-ISSN
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Volume of the periodical
16
Issue of the periodical within the volume
36
Country of publishing house
GB - UNITED KINGDOM
Number of pages
9
Pages from-to
6809-6817
UT code for WoS article
000445220100024
EID of the result in the Scopus database
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