Several methods for the preparation of long-chain vicinal diketones are examined. The acyloincondensation, followed by oxidation, provides an excellent route to symmetrical compounds but is not satisfactory for unsymmetrical diketones. The latter are prepared (i) from dialkylacetylenes by semihydrogenation, hydroxylation, and oxidation with aqueous N-bromosuccinimide; and (ii) from an α-acetoxy-acid
Copper/Iodine‐Cocatalyzed C‐C Cleavage of 1,3‐Dicarbonyl Compounds Toward 1,2‐Dicarbonyl Compounds
作者:Li‐Sha Chen、Lu‐Bing Zhang、Yue Tian、Jin‐Heng Li、Yong‐Quan Liu
DOI:10.1002/ejoc.202000795
日期:2020.9.14
DMSO multi‐tasking enabled a copper/I2‐cocatalyzed transformations of 1,3‐dicarbonyl compounds to 1,2‐dicarbonyl compound is depicted. This method is achieved through a sequence of C–C oxidative cleavage and CO release using DMSO as oxidant, oxygen source and solvent, which is general to a wide range of 1,3‐dicarbonyl compounds, including 1,3‐diketones, 1,3‐keto esters and 1,3‐keto amides, with excellent
DMSO多任务处理实现了铜/ I 2催化的1,3-二羰基化合物向1,2-二羰基化合物的转化。该方法是通过使用DMSO作为氧化剂,氧气源和溶剂的一系列C–C氧化裂解和CO释放来实现的,该过程通常适用于各种1,3-二羰基化合物,包括1,3-二酮,1, 3-酮酸酯和1,3-酮酸酯,具有出色的选择性和广泛的官能团耐受性。
Dimethyl Sulfoxide as an Oxygen Atom Source Enabled Tandem Conversion of 2‐Alkynyl Carbonyls to 1,2‐Dicarbonyls
作者:Yuan Lu、Mu‐Jia Luo、Ming Hu、Yang Li、Jin‐Heng Li
DOI:10.1002/adsc.202000066
日期:2020.4.27
compounds by means of a CuBr2/I2/DMSO/water system is developed, enabling the fromation of various functionalized 1,2‐dicarbonyl compounds, including 1,2‐diketones, α‐keto amides and α‐keto ester. This Cu‐promoted iodine‐mediated tandem procedure employs DMSO as the oxygen atom source of the formed carbonyl group through iodonium ion formation, nucleophilic DMSO addition and C−C bond cleavage cascades.
开发了通过CuBr 2 / I 2 / DMSO /水系统串联2-炔基羰基化合物的方法,使各种官能化的1,2-二羰基化合物(包括1,2-二酮,α-酮酰胺)形成和α-酮酸酯 此铜促进的碘介导的串联过程使用DMSO作为碘原子离子形成,亲核DMSO加成和CC键断裂级联反应形成的羰基的氧原子源。
Ru-Catalyzed Oxidation of Acetylenes to α-Diketones with Iodosylbenzene
作者:Paul Müller、José Godoy
DOI:10.1002/hlca.19810640807
日期:1981.12.16
Disubstituted acetylenes are oxidized with PhIO in presence of Ru-catalysts to afford α-diketones in 65–85% yield. Under the same conditions terminal acetylenes are cleaved to carboxylic acids.
The nitroaldol (Henry) reaction of 2-oxoaldehydes with a variety of nitroalkanes, under basic heterogeneous conditions and microwave irradiation, affords 1,2-diketones in a one-pot way.