Cai, Mao; Xu, Kaini; Li, Yuze; Nie, Zongxiu; Zhang, Long; Luo, Sanzhong published their research in Journal of the American Chemical Society in 2021. The article was titled 《Chiral Primary Amine/Ketone Cooperative Catalysis for Asymmetric α-Hydroxylation with Hydrogen Peroxide》.Quality Control of Ethyl 2-methyl-3-oxobutanoate The article contains the following contents:
Carbonyls and amines are yin and yang in organocatalysis as they mutually activate and transform each other. These intrinsically reacting partners tend to condense with each other, thus depleting their individual activity when used together as cocatalysts. Though widely established in many prominent catalytic strategies, aminocatalysis and carbonyl catalysis do not coexist well, and, as such, a cooperative amine/carbonyl dual catalysis remains essentially unknown. Here we report a cooperative primary amine and ketone dual catalytic approach for the asym. α-hydroxylation of β-ketocarbonyls with H2O2. Besides participating in the typical enamine catalytic cycle, the chiral primary amine catalyst was found to work cooperatively with a ketone catalyst to activate H2O2 via an oxaziridine intermediate derived from an in-situ-generated ketimine. Ultimately, this enamine-oxaziridine coupling facilitated the highly controlled α-hydroxylation of several β-ketocarbonyls in excellent yield and enantioselectivity. Notably, late-stage hydroxylation for peptidyl amide or chiral esters can also be achieved with high stereoselectivity. In addition to its operational simplicity and mild conditions, this cooperative amine/ketone catalytic approach also provides a new strategy for the catalytic activation of H2O2 and expands the domain of typical amine and carbonyl catalysis to include this challenging transformation. The experimental part of the paper was very detailed, including the reaction process of Ethyl 2-methyl-3-oxobutanoate(cas: 609-14-3Quality Control of Ethyl 2-methyl-3-oxobutanoate)
Ethyl 2-methyl-3-oxobutanoate(cas: 609-14-3) belongs to ketone compounds. Ketones are highly reactive, although less so than aldehydes, to which they are closely related. Much of their chemical activity results from the nature of the carbonyl group. Ketones readily undergo a wide variety of chemical reactions.Quality Control of Ethyl 2-methyl-3-oxobutanoate
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