通过无过渡金属的一锅两步程序制备了各种官能化三芳基甲烷和1,1-二芳基烷烃衍生物,其中包括各种二乙酸苯亚缩酯与有机锌试剂的反应。通过将溶剂从 THF 更改为甲苯,可以实现顺序交叉偶联,并提出了两步 S N 1 型机理,并通过实验研究证明了这一点。该方法的合成效用通过几种生物学相关分子的合成得到进一步证明,例如抗结核剂、抗乳腺癌剂、鞘氨醇-1-磷酸(S1P)受体调节剂的前体和FLAP抑制剂。
metal‐free aerobic oxidative cross‐coupling reaction between a benzylic C(sp3)–H bond and a carboxylic acidcatalyzed by 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone and tert‐butyl nitrite has been developed. This protocol provides a mild and efficient route to obtain diarylmethanol esters and phthalides. It can be regarded as a typical example of green chemistry in oxidative C–O coupling.
DDQ-Catalyzed Oxidative CO Coupling Of sp<sup>3</sup>CH Bonds With Carboxylic Acids
作者:Hong Yi、Qiang Liu、Jie Liu、Ziqi Zeng、Yuhong Yang、Aiwen Lei
DOI:10.1002/cssc.201200458
日期:2012.11
catalytic amounts of DDQ combined with MnO2 as oxidant, an efficient oxidative CO coupling of benzylic sp3 CH bonds with carboxylic acids affords a series of carboxylic esters in 70–98 % yields. A wide range of functional groups and various carboxylic acids are tolerated. The reaction involves both CH functionalization and CO bond formation.
A Novel Synthesis of Esters via Substitution of the Benzotriazolyl Group in 1-(Benzotriazol-1-yl)alkyl Esters with Organozinc Reagents
作者:Alan R. Katritzky、Stanislaw Rachwal、Bogumila Rachwal
DOI:10.1055/s-1991-26382
日期:——
Aldehydes are converted by thionyl chloride and benzotriazole into 1-(1-chloroalkyl)benzotriazoles which react with sodium carboxylates to give 1-(benzotriazol-1-yl)alkyl esters 3. In an alternative route, 3 are prepared by substitution of one of the acetoxy groups in acylals with benzotriazole. The benzotriazolyl moiety in 3 is substituted by an alkyl, an aryl or an alkynyl group upon treatment with an organozinc reagent in a new versatile synthesis of esters 4.