7635-54-3Relevant articles and documents
Concise synthesis and applications of enantiopure spirobiphenoxasilin-diol and its related chiral ligands
Liu, Tao,Wang, Biqin,Wang, Peng,Wu, Yichen,Xu, Wen-Qiang,Yang, Lei
supporting information, p. 13365 - 13368 (2021/12/17)
The development of chiral architectures for chiral ligand and catalyst discovery is essential for asymmetric catalysis. Herein, we report the concise synthesis of a Si-centered spirocyclic skeleton, spirobiphenoxasilin-diol (SPOSiOL), and its derived chiral ligands. Using the chemical resolution method, the optical SPOSiOL could be obtained in high yield on a gram scale. Preliminary studies indicated that this ligand scaffold has great potential in transition metal-catalyzed asymmetric reactions. This finding further highlights that the Si-centered spirocyclic scaffolds are of great value in asymmetric catalysis. This journal is
Preparation method of alicyclic and aromatic-aliphatic chloroformate
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Paragraph 0025; 0032-0033, (2017/05/16)
The invention belongs to the technical field of fine chemistry, and in particular relates to a preparation method of alicyclic and aromatic-aliphatic chloroformate. The preparation method is characterized in that alicyclic alcohol chloroformate or aromatic-aliphatic alcohol chloroformate is obtained by taking alicyclic alcohol or aromatic-aliphatic alcohol and bis(trichlormethyl)carbonate as raw materials, taking organic base as a catalyst and reacting in an organic solvent under certain reaction temperature and certain reaction time, wherein molar ratio among the alicyclic alcohol or the aromatic-aliphatic alcohol, the bis(trichlormethyl)carbonate and the organic base is 1 to (0.4 to 1) to (1.2 to 3); experiment time and experiment temperature are different in two stages, in the first stage, the reaction temperature is -10 to 0 DEG C, and the reaction time is 2 to 5 hours; in the second stage, the reaction temperature is 0 to 25 DEG C, and the reaction time is 7 to 13 hours; a mass ratio between the organic solvent and the alicyclic alcohol or the aromatic-aliphatic alcohol is (10 to 25) to 1; residue in a reaction system is effectively treated, and reaction waste is also recycled and utilized. The preparation method disclosed by the invention has the characteristics of stable reaction, high reaction yield and product purity, environment protection of a reaction process, low production cost, less emission of three wastes, simpleness in preparation technology and easiness in industrialization.
Synthesis of chiral diazanedicarboxylate and diazenedicarboxylate esters: electrophilic amination reactions of achiral ester and amide enolates
Harris, Joanna M.,Bolessa, Evon A.,Mendonca, Aubrey J.,Feng, Sheng-Chu,Vederas, John C.
, p. 1945 - 1950 (2007/10/02)
A series of chiral dialkyl (bornyl, isobornyl, menthyl) diazenedicarboxylates 4a-c were prepared by conversion of the corresponding alcohols into chloroformates, condensation with hydrazine, and oxidation of the corresponding dialkyl diazanedicarboxylates 3a-c with N-bromosuccinimide and pyridine (50-90percent yield).Their reaction with achiral enolates of esters and N,N-dimethyl amides at -70 deg C gave α-hydrazino acid derivatives with little or no stereoselectivity.Analogous amination of chiral oxazolidinone (Evans enolate) anions were highly selective, but were controlled exclusively by enolate geometry.