Ueber einen Aldehyd‐Alkohol

Abstract

Wu r tz: Ueber einen Aldehyd-Alkohol. 457 di 0 bet reffend e Oriyi nalabha nd I u ng (Corn p t. rend. 7 I, 462) zu Gesicht zu bekommen. Ails einer kurzen Bemerkung in der letztern schliesse ioh nun, dass die genannten Cherniker die oben beschriebene Aethylurarnidobeneoesaure ebenfalls bereits beobrchtet haben niiissen, indem sie sagen, dass sich auch ,,die t'reie ArnidobenzoEsaure, Amidocuminsiiure u n d Amidoanissaure mit cyansaurem Aethyl verbinden konnen und dnss die dabei entstehenden Korper denjenigen aus den betreffenden Aethern sehr iihnlich seien."

Quinidine Thiourea‐Catalyzed Aldol Reaction of Unactivated Ketones: Highly Enantioselective Synthesis of 3‐Alkyl‐3‐hydroxyindolin‐2‐ones

“…[3] The mechanism is usually a combination of both covalent and noncovalent catalyses, since most of these catalysts also contain a hydrogen-bonding moiety to direct the approach of the enamine acceptor. In contrast, although enol and enolate (Scheme 1, lower equation) are the active intermediates in the original aldol reactions, [4] organocatalyzed enantioselective direct aldol reaction of unactivated ketones through the enolate mechanism is very difficult, because the acidity of the a proton in these ketones is very low. To our knowledge, there has been no such report.…”

Noncovalent catalysis of glucose-containing imidazolium salt in solvent-free one-pot synthesis of Ortho-aminocarbonitriles

“…[3][4][5] The main reason is that the formation of interdiate from the substrate and the noncovalent cataltyst is easier than the covalent one due to the low orbital overlap between the substrate and the noncovalent cataltyst. 4,6 Glucose is an important nature product bearing five hydroxyl groups.…”

Quinidine Thiourea‐Catalyzed Aldol Reaction of Unactivated Ketones: Highly Enantioselective Synthesis of 3‐Alkyl‐3‐hydroxyindolin‐2‐ones

“…3 The mechanism is usually a combination of both covalent and noncovalent catalyses since most of these catalysts also contain a hydrogen bonding moiety to direct the approach of the enamine acceptor. In contrast, although enol and enolate (Scheme 1, lower equation) are the active intermediates in the original aldol reactions, 4 organocatalyzed enantioselective direct aldol reaction of unactivated ketones via the enolate mechanism is very difficult, because the acidity of the α-proton in these ketones is very low. To our knowledge, there has been no such report.…”