37009-54-4Relevant academic research and scientific papers
Synthesis of α-Amidoketones through the Cascade Reaction of Carboxylic Acids with Vinyl Azides under Catalyst-Free Conditions
Gao, Cai,Zhou, Qianting,Yang, Li,Zhang, Xinying,Fan, Xuesen
, p. 13710 - 13720 (2020/11/13)
An efficient synthesis of α-amidoketone derivatives through the cascade reactions of carboxylic acids with vinyl azides is presented. Compared with literature protocols, notable features of this new method include catalyst-free conditions, broad substrate scope, good tolerance of a wide range of functional groups, and high efficiency. In addition, the synthetic potential of this method as a tool for late-stage modification was convincingly manifested by its application in the structural elaborations of a number of carboxylic acid drug molecules.
Synthesis method of alpha-acylamino ketone compound
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Paragraph 0027-0029; 0030-0032; 0036, (2020/12/08)
The invention discloses a synthesis method of an alpha-acylamino ketone compound, and belongs to the technical field of organic synthesis. The preparation method comprises the following steps: mixingan alkenyl azide compound 1, a carboxylic acid compound 2 and an organic solvent, and heating to react to obtain the alpha-acylamino ketone compound 3. Compared with the prior art, the method has thefollowing advantages: (1) the synthesis process is simple and efficient, no catalyst is needed in the whole process, and the alpha-acylamino ketone compound can be obtained with high yield by dissolving the alkenyl azide compound and the carboxylic acid compound in the solvent and stirring; (2) raw materials are cheap and easy to obtain, reaction conditions are mild, and operation is simple; (3) the substrate is wide in application range and can be used for modifying drug molecules; and (4) the atom economy is high, and the requirements of green chemistry are met.
Stereoselective synthesis of 2-aminocyclobutanols via photocyclization of α-amido alkylaryl ketones: Mechanistic implications for the Norrish/Yang reaction
Griesbeck, Axel G.,Heckroth, Heike
, p. 396 - 403 (2007/10/03)
A series of chiral N-acylated α-amino p-methylbutyrophenone derivatives 1a-1h was synthesized from α-amino acids via a three-step procedure. These substrates were photolyzed in benzene and gave Norrish II and Norrish I cleavage products as well as the N-acylated 2-aminocyclobutanols that derive from γ-hydrogen abstraction and 1,4-triplet biradical combination (Yang cyclization). The products were formed with characteristic Yang/cleavage ratios. The quantum yields for the photodecomposition of the N-acetyl-protected substrates 1b,e,f were moderate (12-26%); the diastereoselectivities of the cyclobutanol formation were remarkably high for all substrates. High diastereospecificity was observed for the isoleucine derivatives (2S,3S)-1g and allo-(2S,3R)-1g; the Yang reaction dominated the photochemistry of allo-1g, whereas 1g gave preferentially Norrish II cleavage. The role of hydrogen bonding as one of the stereo-directing effects was demonstrated by comparison of the cyclization efficiency of the valine derivative 1e with 1h,i,j. Also, aromatic β-keto esters gave the Yang cyclization products in low yields. The diastereoselectivity of the cyclobutanol formation was rationalized by a three-step mechanism where every step is connected with one distinct stereochemical induction mechanism: (a) diastereoselective hydrogen abstraction, (b) conformational equilibration of the 1,4-tetramethylene biradicals (as calculated by semiempiric methods) controlled by hydrogen bonding, and (c) diastereoselective biradical combination (versus cleavage) influenced by spin-orbit coupling controlled intersystem crossing geometries.
