196883-45-1

Upstream product

• 7677-24-9 trimethylsilyl cyanide 
• 27845-50-7 (E)-N-benzylidenebenzylamine 
• 74-90-8 hydrogen cyanide 
• 100-52-7 benzaldehyde 
• 100-46-9 benzylamine 
• 780-25-6 N-benzylidene benzylamine 

Relevant academic research and scientific papers

N-Salicyl-β-aminoalcohols as a new class of ligand for catalytic asymmetric Strecker reactions

An enantioselective Strecker synthesis employing novel chiral titanium complex catalysts derived from structurally simple chiral N-salicyl-β-amino alcohols is described. Reactions of N-benzylidenebenzylamine with trimethylsilyl cyanide in the presence of the catalyst (10 mol%) gave the corresponding α-aminonitrile in good to excellent yields, along with relatively high enantioselectivity (up to 86% ee). Similar reactions with various imines derived from aromatic aldehydes resulted in moderate to good enantioselectivity (44-81% ee).

Reversal of enantioselectivity by catalyst protonation: Asymmetric hydrocyanation of imines with oxazaborolidines

A new application of chiral oxazaborolidines in asymmetric transformation, namely the hydrocyanation of imines, is described. The effect of protonation of these catalysts on the reactivity and enantioselectivity of hydrocyanations is studied. Significant

Highly Active Chiral Dilithium(I) Binaphthyldisulfonate Catalysts for Enantio- And Chemoselective Strecker-Type Reactions

An enantioselective Strecker-type reaction of aldimines and ketimines was developed by using a chiral dilithium(I) binaphthyldisulfonate as a chiral acid-base cooperative catalyst. The present catalytic system features an extremely short reaction time (10 min to 4 h), unlike conventional catalytic systems. Along with the design of stronger chiral Li(I) Lewis acid catalysts, a highly reactive pentacoordinate silicate generated in situ could promote the reactions. In particular, instead of unstable N-Bn Strecker products, more stable N-CH2(9-anthryl) and N-CH2(1-naphthyl) Strecker products could be obtained in high yields with high enantioselectivities. By a switch of the present and previous catalyst systems, chemoselective cyanation to a ketoaldimine could be performed, respectively. Moreover, mechanistic investigations provided useful information regarding the active catalysts, catalytic cycles, and possible transition states.

Enantioselective Strecker reaction of aldimines using potassium cyanide catalyzed by a recyclable macrocyclic V(v) salen complex

A chiral dimeric macrocyclic V(v) salen complex based on a chiral macrocyclic salen ligand derived from 1R, 2R-(-) diaminocyclohexane with trigol bisaldehyde was synthesized and evaluated as an efficient catalyst (5 mol%) for asymmetric addition of potass

Enantioselective hydrocyanation of N-protected aldimines

Enantioselective hydrocyanation of N-benzyloxycarbonyl aldimines catalyzed by a Ru[(S)-phgly]2[(S)-binap]/C6H5OLi system or a bimetallic complex [Li{Ru[(S)-phgly]2[(S)-binap]}]Cl affords the amino nitriles in 92 - 99% ee. The reaction is carried out in tert-C 4H9OCH3 with a substrate-to-catalyst molar ratio in the range of 500 - 5000 at -20 to 0°C. Primary, secondary, and tertiary alkyl imines as well as the aryl and heteroaryl substrates are smoothly cyanated to produce the desired products in high yield.

Self-supported chiral titanium cluster (SCTC) as a robust catalyst for the asymmetric cyanation of imines under batch and continuous flow at room temperature

A robust heterogeneous self-supported chiral titanium cluster (SCTC) catalyst and its application in the enantioselective imine-cyanation/Strecker reaction is described under batch and continuous processes. One of the major hurdles in the asymmetric Strecker reaction is the lack of availability of efficient and reusable heterogeneous catalysts that work at room temperature. We exploited the readily hydrolyzable nature of titanium alkoxide to synthesize a self-supported chiral titanium cluster (SCTC) catalyst by the controlled hydrolysis of a preformed chiral titanium-alkoxide complex. The isolated SCTC catalysts were remarkably stable and showed up to 98% enantioselectivity (ee) with complete conversion of the imine within 2 h for a wide variety of imines at room temperature. The heterogeneous catalysts were recyclable more than 10 times without any loss in activity or selectivity. The robustness, high performance, and recyclability of the catalyst enabled it to be used in a packed-bed reactor to carry out the cyanation under continuous flow. Up to 97% ee and quantitative conversion with a throughput of 45 mgh-1 were achieved under optimized flow conditions at room temperature in the case of benzhydryl imine. Furthermore, a three-component Strecker reaction was performed under continuous flow by using the corresponding aldehydes and amines instead of the preformed imines. A good product distribution was obtained for the formation of amino nitriles with ee values of up to 98%. Synthetically useful ee values were also obtained for challenging α-branched aliphatic aldehyde by using the three-component continuous Strecker reaction.

Highly enantioselective titanium-catalyzed cyanation of imines at room temperature

(Figure presented) A highly active and enantioselective titanium-catalyzed cyanatlon of imines at room temperature Is described. The catalyst used Is a partially hydrolyzed titanium alkoxide (PHTA) precatalyst together with a readily available N-salicyl-β-aminoalcohol ligand. Up to 98% ee was obtained with quantitative yields In 15 min of reaction time using 5 mol % of the catalyst. Various N-protecting groups such as benzyl, benzhydryl, Boc, and PMP are tolerated.

TITANIUM COMPOUNDS AND PROCESS FOR CYANATION OF IMINES

The present invention relates to titanium catalysts for synthesis reactions produced by bringing a reaction mixture comprising a titanium alkoxide and a ligand in contact with water, wherein the ligand is represented by the general formula (e), wherein R1, R2, R3, and R4 are independently a hydrogen atom, an alkyl group, or the like, and (A) represents a group with two or more carbon atoms. The titanium catalysts may be isolated in solid form and may be stored. The invention further relates to a process for cyanation of imines, wherein the process comprises reacting an imine with a cyanating agent in the presence of the titanium catalyst.

Mn(III) salen complexes-catalyzed enantioselective addition of trimethyl silylcyanide to N-benzylimines in the presence of 4-phenyl pyridine-N-oxide as an additive

Chiral monomeric and dimeric Mn(III) salen complexes viz., [(S,S)-N,N′-bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediaminato manganese(III) chloride and 5,5-methylene di-[(S,S)-{N-(3-tert-butyl salicylidine)-N′-(3′,5′-di-tert-butyl salicylidene)}-1,

A remarkable titanium-catalyzed asymmetric strecker reaction using hydrogen cyanide at room temperature

Close to perfect enantioselectivity (up to 98% ee) is obtained for the formation of amino nitrites using hydrogen cyanide (HCN) as the cyanide source at room temperature for the first time. In an operationally simple process, the catalyst generated from a partially hydrolyzed titanium alkoxide (PHTA) and (S)-N-salicyl-ss-amino alcohol ligand, catalyzes the cyanation of imines in a short reaction time.