Acyclic stereoselection in the alkylation of chiral dipole-stabilized organolithiums: a self-immolative chirality transfer process for the synthesis of primary amines
The reaction of β-amino alcohols with 1,1′-carbonyldiimidazole in dichloromethane is affected by the size of the nitrogen substituent. 1,3-Oxazolidin-2-ones are exclusively obtained from N-H, N-methyl and N-arylmethyl derivatives. O-(1-Imidazolyl)carbonyl derivatives are formed as intermediates from N-[1-(2-pyridyl)alkyl]-(S)-valinol and are mainly or exclusively converted into aziridines in the presence
β-氨基醇与 1,1'-羰基二咪唑在二氯甲烷中的反应受氮取代基大小的影响。1,3-Oxazolidin-2-ones 仅从 NH、N-甲基和 N-芳甲基衍生物中获得。O-(1-咪唑基)羰基衍生物作为中间体由 N-[1-(2-吡啶基)烷基]-(S)-缬氨醇形成,主要或仅在水存在下转化为氮丙啶,尽管环化是被三苯甲基等大的 N 取代基阻碍。
Carbon Dioxide as a Carbonylating Agent in the Synthesis of 2-Oxazolidinones, 2-Oxazinones, and Cyclic Ureas: Scope and Limitations
Carbon dioxide can be used as a convenient carbonylating agent in the synthesis of 2-oxazolidinones, 2-oxazinones, and cyclic ureas. The transient carbamate anion generated by treating a primary or secondary amine group in basic media can be activated with phosphorylatingagents such as Diphenylphosphoryl azide (DPPA) and Diphenyl chlorophosphate (DPPCl) but also with other types of electrophiles such
Ring Opening Reactions of<i>N</i>-Alkyl Oxazolidinones with Organolithium Reagents
作者:Simon Jones、Helen C. Norton
DOI:10.1055/s-2003-44972
日期:——
Addition of primary, secondary and aryl organolithium reagents to N-methyl and N-benzyl oxazolidin-2-ones give N-acyl amino alcohols in 30-93% yields. Application to the synthesis of an imidazoyl oxazoline is demonstrated.
Potassium trimethylsilanolate induced cleavage of 1,3-oxazolidin-2- and 5-ones, and application to the synthesis of (R)-salmeterol
作者:Diane M. Coe、Rossana Perciaccante、Panayiotis A. Procopiou
DOI:10.1039/b212454h
日期:2003.3.27
A convenient and efficient method for the cleavage of 1,3-oxazolidin-5-ones and 1,3-oxazolidin-2-ones utilising potassium trimethylsilanolate in tetrahydrofuran is described. The benzyloxycarbonyl-protecting group is readily removed under the reaction conditions, whereas the N-benzoyl group is stable. A synthesis of (R)-salmeterol exploiting the 2-oxazolidinone ring as a protecting group for the ethanolamine moiety is also described.
Decarboxylative ring-opening of 2-oxazolidinones: a facile and modular synthesis of β-chalcogen amines
作者:Fábio Z. Galetto、Cleiton da Silva、Ricardo I. M. Beche、Renata A. Balaguez、Marcelo S. Franco、Francisco F. de Assis、Tiago E. A. Frizon、Xiao Su
DOI:10.1039/d2ra06070a
日期:——
We report herein the synthesis of primary and secondary β-chalcogen amines through the regioselective ring-opening reaction of non-activated 2-oxazolidinones promoted by in situ generated chalcogenolate anions. The developed one-step protocol enabled the preparation of β-selenoamines, β-telluroamines and β-thioamines with appreciable structural diversity and in yields of up to 95%.