338461-66-8

Upstream product

• 4406-72-8 2-phenyl[1,3,2]dioxaborolane 
• 89232-30-4 (2E)-N-benzylbut-2-enamide 
• 98-80-6 phenylboronic acid 
• 100-46-9 benzylamine 
• 1196-67-4 (E)-β-methylcinnamaldehyde 
• 1196-67-4 3-phenyl-2-butenal 
• 2393-23-9 4-methoxy-benzylamine 
• 2996-92-1 phenyl trimethylsiloxane 
• 24388-23-6 2-phenyl-4,4,5,5-tetramethyl-1,3,2-dioxoborole 

Relevant academic research and scientific papers

Efficient access to chiral β-arylamides via asymmetric 1,4-additions of potassium trifluoro(organo)borates

This paper describes an efficient enantioselective conjugate addition of highly stable potassium trifluoro(organo)borates to α,β-unsaturated amides. This reaction, catalyzed by chiral rhodium(I) complexes affords Michael adducts with high yields and enant

Rhodium(I)-catalyzed asymmetric 1,4-addition of arylboronic acids to α,β-unsaturated amides

The conjugate addition of arylboronic acids to α,β-unsaturated amides was carried out in the presence of a chiral rhodium catalyst and an aqueous base. The catalyst prepared in situ from Rh(acac)(CH2=CH2)2 and (S)-binap provided (R)-N-benzyl-3-phenylbutanamide with 93% ee in the addition of phenylboronic acid to N-benzyl crotonamide. The reaction suffered from incomplete conversion resulting in moderate yields, but addition of an aqueous base, such as K2CO3 (10-50 mol%) was found to be highly effective to improve the chemical yields. The role of the base giving a RhOH species active for transmetalation with arylboronic acids was discussed.

Enantioselective Hydroamidation of Enals by Trapping of a Transient Acyl Species

An enantioselective synthesis of β-chiral amides through asymmetric and redox-neutral hydroamidation of enals is reported. In this reaction, a chiral N-heterocyclic carbene (NHC) catalyst reacts with enals to generate the homoenolate intermediate. Upon highly enantioselective β-protonation through proton-shuttle catalysis, the resulting azolium intermediate reacts with imidazole to yield the key β-chiral acyl species. This transient intermediate provides access to diversified β-chiral carbonyl derivatives, such as amides, hydrazides, acids, esters, and thioesters. In particular, β-chiral amides can be prepared in excellent yield and ee (40 chiral amides, up to 95 % yield and 99 % ee). This modular strategy overcomes the challenge of disruption of the highly selective proton-shuttling process by basic amines.

Asymmetric 1,4-addition of aryltrialkoxysilanes to α,β-unsaturated esters and amides catalyzed by a chiral rhodium complex

A highly enantioselective 1,4-addition of aryltrialkoxysilanes to α,β-unsaturated esters and amides was successfully catalyzed by a chiral rhodium complex generated from [Rh(cod)(MeCN)2]BF4 and (S)-BINAP.

Rhodium/diene-catalyzed asymmetric 1,4-addition of arylboronic acids to α,β-unsaturated Weinreb amides

Rhodium/chiral diene (S,S)-3b complex has been found to effectively catalyze the 1,4-addition of arylboronic acids to α,β-unsaturated Weinreb amides, furnishing useful β-chiral Weinreb amides in high enantioselectivity. The Royal Society of Chemistry 2005.

Rhodium-catalyzed 1,4-addition of arylboronic acids to α,β-unsaturated carbonyl compounds: Large accelerating effects of bases and ligands

The effects of ligands and bases in the rhodium(I)-catalyzed 1,4-addition of arylboronic acids to α,β-unsaturated carbonyl compounds were reinvestigated to carry out the reaction under mild conditions. Rhodium(I) complexes possessing a 1,5-cyclooctadiene (cod) and a hydroxo ligand such as [RhOH(cod)]2 exhibited excellent catalyst activities compared to those of the corresponding rhodium-acac or -chloro complexes and their phosphine derivatives. The reaction was further accelerated in the presence of KOH, thus allowing the 1,4-addition even at 0 °C. A cationic rhodium-(I)-(R)-binap complex, [Rh(R-binap)(nbd)]BF4, catalyzed the reaction at 25-50 °C in the presence of Et3N with high enantioselectivities of up to 99% ee for α,β-unsaturated ketones, 92% for aldehydes, 94% for esters, and 92% for amides.