86000-11-5Relevant academic research and scientific papers
Synthesis of β2,2-Amino Esters via Rh-Catalysed Regioselective Hydroaminomethylation
Cunillera, Anton,Ruiz, Aurora,Godard, Cyril
, p. 4201 - 4207 (2019/08/01)
The synthesis of β2,2-amino esters was successfully achieved via Rh-catalysed regioselective hydroaminomethylation of methyl methacrylate with secondary amines using the neutral precursor [Rh(acac)(CO)2]. In this process, the presence of molecular sieves revealed crucial in order to access the final amino ester. For the synthesis of products containing aniline derivatives, the use of the cationic precursor [Rh(COD)2]BF4 and MeCgPPh phosphine as ligand was necessary in a mixture of toluene/DCE as solvent. Effects of the steric and electronic properties of the amines were observed during this study. Interestingly, poisoning effect of CO in the hydrogenation of the imine intermediate was observed when benzyl amine was used. (Figure presented.).
Highly regioselective rhodium-catalysed hydroformylation of unsaturated Esters: The first practical method for quaternary selective carbonylation
Clarke, Matthew L.,Roff, Geoffrey J.
, p. 7978 - 7986 (2007/10/03)
Highly regioselective hydroformylation of unsaturated esters can be achieved when a highly reactive, ligand-modified, rhodium catalyst is employed near ambient temperatures (15-50°C) and pressures over 30 bar. The use of 1,3,5,7-tetramethyl-2,4,8-trioxa-6-phosphaadamantane shows distinct advantages over other commonly applied phosphanes in terms of reaction rate, and regio- and chemoselectivity. Hydroformylation of a range 1,1-di- and 1,1,2-trisubstituted unsaturated esters yields quaternary aldehydes that are forbidden products according to Keulemans Rule. The aldehydes can be reductively aminated with molecular hydrogen to give β-amino acid esters in high yield. The overall green chemical process involves converting terminal alkynes into unusual β-amino acid esters with only water generated as an essential byproduct. This catalytic system has also been applied to the hydroformylation of simple 1,2-disubstitued unsaturated esters, which have been hydroformylated with excellent α-selectivity and good chemo-selectivity for the first time.
Trifluoromethanesulfonic Acid-Promoted Reaction of Hexahydro-1,3,5-triazines. Introduction of a Secondary Aminomethyl Grouping into Carboxylates at the α-Position through Ketene Silyl Acetals
Ikeda, Kiyoshi,Achiwa, Kazuo,Sekiya, Minoru
, p. 1579 - 1583 (2007/10/02)
Introduction of secondary aminomethyl grouping RNHCH2 into carboxylates at the α-position has been achieved by reaction of hexahydro-1,3,5-triazines with ketene silyl acetals in the presence of a catalytic amount of trifluoromethanesulfonic acid.Keywords
TRIFLUOROMETHANESULFONIC ACID-PROMOTED REACTION OF HEXAHYDRO-1,3,5-TRIAZINES WITH KETENE SILYL ACETALS. CONVENIENT SYNTHESIS OF ALKYL β-AMINOCARBOXYLATES
Ikeda, Kiyoshi,Achiwa, Kazuo,Sekiya, Minoru
, p. 913 - 916 (2007/10/02)
A new, convenient synthesis of alkyl β-aminocarboxylates has been achieved by a reaction of hexahydro-1,3,5-triazines with ketene silyl acetals in the presence of catalytic amount of trifluoromethanesulfonic acid.
