Organocatalytic asymmetric nitroaldol reaction: Cooperative effects of guanidine and thiourea functional groups

Chemistry - An Asian Journal

Volumn 2, Issue 9, 2007, Pages 1150-1160

  Sohtome, Yoshihiro ^b   Takemura, Nobuko ^a   Takada, Keisuke ^a   Takagi, Rika ^a   Iguchi, Toshitsugu ^a   Nagasawa, Kazuo ^a  

^a TOKYO UNIVERSITY OF AGRICULTURE AND TECHNOLOGY   (Japan)

^b UNIVERSITY OF TOKYO   (Japan)

Author keywords

Chemoselectivity guanidine; Nitroaldol reaction; Organocatalysis; Surfactants

Indexed keywords

3-HYDROXYBUTANAL; ALDEHYDE; ALDOL; GUANIDINE; THIOUREA; UNCLASSIFIED DRUG;

ARTICLE; CATALYSIS; CHEMISTRY; LIQUID CHROMATOGRAPHY; NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY;

ALDEHYDES; CATALYSIS; CHROMATOGRAPHY, LIQUID; GUANIDINE; MAGNETIC RESONANCE SPECTROSCOPY; THIOUREA;

EID: 34548556420     PISSN: 18614728     EISSN: 1861471X     Source Type: Journal    
DOI: 10.1002/asia.200700145     Document Type: Article

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172. 1H NMR signals.
173. In the absence of KOH, the reaction did not proceed at all. Furthermore, no reaction occurred after pretreatment of 1a with an excess of KOH (10 equiv with respect to 1a). KOH might deprotonate nitroalkane in this catalytic system.
174. a) Toluene is the best organic solvent in this biphasic system.
175. 2O: 6%, 17% ee.
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177. [20i.o]
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203. The differences in reactivity and selectivity cannot be attributed the three-dimensional structure of 1, because the NMR spectra are quite similar.
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