This article describes an efficient method of bromination of organicsubstrates including aromatics, alkenes and alkynes with NH4VO3 as a catalyst and H2O2 as an oxidant agent using a non-toxic and easy-to-handle source of bromine, tetrabutylammonium bromide. The process was developed under mild reaction conditions and is an innovation from reported methods in aspects such as: i) short reaction times
本文介绍了一种有效的方法,该方法使用无毒且易于处理的溴,四丁基铵源,以NH 4 VO 3为催化剂,H 2 O 2为氧化剂,对包括芳族化合物,烯烃和炔烃在内的有机底物进行溴化。溴化物。该方法是在温和的反应条件下开发的,并且是从已报道方法的创新,例如:i)反应时间短,ii)在室温下工作的能力,iii)区域选择性和高产率。
A CONVENIENT SYNTHESIS OF α-BROMOKETONES FROM OLEFINS
α-Bromoketones are prepared in good yields by the reaction of olefins with sodium bromite in aqueous acetic acid at room temperature.
α-溴酮通过烯烃与溴化钠在乙酸水溶液中在室温下反应制备,收率良好。
Ni-Catalyzed Formal Cross-Electrophile Coupling of Alcohols with Aryl Halides
作者:Quan Lin、Guobin Ma、Hegui Gong
DOI:10.1021/acscatal.1c04239
日期:2021.11.19
and TBAB as the mild bromination reagents enables rapid transformation of a wide range of alcohols to their bromide counterparts within one to 5 min in CH3CN and DMF, which is compatible with the Ni-catalyzed cross-electrophile coupling conditions in the presence of a chemical reductant. The present method is suitable for arylation of a myriad of structurally complex alcohols with no need for prepreparation
未活化醇的直接偶联仍然是当前合成化学中的一个挑战。我们在此展示了一种建立在醇与芳基卤化物的原位卤化/还原偶联以形成 Csp 2 -Csp 3键的策略。2-氯-3-乙基苯并[ d ]恶唑-3-鎓盐 (CEBO) 和 TBAB 作为温和溴化试剂的组合能够在 CH 3 中在一到 5 分钟内将范围广泛的醇快速转化为其溴化物对应物CN 和 DMF,在化学还原剂存在下与 Ni 催化的交叉亲电偶联条件相容。本方法适用于无数结构复杂的醇的芳基化,而无需制备卤代烷。更重要的是,温和且动力学快速的溴化过程在对称二醇的溴化/芳基化和多元醇中较少的空间位阻羟基中显示出良好的选择性,从而为二醇和多元醇的选择性官能化提供了希望,而无需费力的保护/脱保护操作。这项工作的实用性在许多碳水化合物、药物化合物和天然醇的芳基化中也很明显。
Complexes of cis-dioxomolybdenum(VI) with a chiral tetradentate tripodal-like ligand system: Syntheses, structures and catalytic activities
作者:Sabari Ghosh、Sathish Kumar Kurapati、Samudranil Pal
DOI:10.1016/j.poly.2016.08.025
日期:2017.3
In each complex, the chiral (bzacL n ) 2− acts as a tetradentate, N 2 O 2 -donor, tripodal-like ligand system and along with the two mutually cis oxo groups forms a distorted octahedral N 2 O4 coordination environment around the molybdenum(VI) center. All four complexes are diamagnetic and non-electrolytic. The infrared spectra are generally consistent with the structural formulas of 1 – 4 . The electronic
g-C<sub>3</sub>N<sub>4</sub>/metal halide perovskite composites as photocatalysts for singlet oxygen generation processes for the preparation of various oxidized synthons
g-C3N4/metal halide perovskite composites were prepared and used for the first time as photocatalysts for in situ 1O2 generation to perform hetero Diels–Alder, ene and oxidation reactions with suitable dienes and alkenes. The standardized methodology was made applicable to a variety of olefinic substrates. The scope of the method is finely illustrated and the reactions afforded desymmetrized hydroxy-ketone
制备了gC 3 N 4 /金属卤化物钙钛矿复合材料,并首次用作原位 1 O 2的光催化剂,以进行杂Diels-Alder,烯烃和与合适的二烯和烯烃的氧化反应。使标准化的方法学适用于各种烯烃底物。很好地说明了该方法的范围,并且反应得到了不对称的羟基酮衍生物,不饱和酮和环氧化物。还观察到一些局限性,特别是在烯烃氧化的情况下,并且在这项工作中观察到较差的化学选择性,这是基于MHP的复合材料在原位 1 O 2中的首次应用代。实验协议可以用作进一步扩展MHP在有机反应中的知识和适用性的平台,因为钙钛矿提供了丰富的调节策略,可用于提高反应产率和选择性。