Hypervalent Iodine in Synthesis XXX: Palladium-Catalyzed Reaction of Diaryliodonium Salts with β-substituted-α, β-enones
摘要:
The reaction of diaryliodonium salts with beta-substituted-alpha,beta-enones in the presence of a palladium catalyst affords H-beta-substituted products with excellent yields.
Mizoroki–Heck reaction of 1,2-disubstituted aryl alkenes: Variables of synthesis, solvent and ligand modulation of reactivity
作者:Pronnoy G. Bangar、Priyanka R. Jawalkar、Swapnil R. Dumbre、Pallavi K. Raut、Dharmaraj J. Patil、Neethu Tv、Shana Sudhakaran、Suresh Iyer
DOI:10.1080/00397911.2020.1811986
日期:2020.12.16
Abstract Reaction of aryl iodides with 1,2-disubstituted aryl alkenes in the presence of TBABr/TBACl gave high yields of the Mizoroki–Heck product. Phosphine ligands were used for the modulation of reactivity and stereoselectivity, for the reaction of 4-iodoanisole with cinnamaldehyde. tert-Bu3P.HBF4 gave the highest E:Z ratio of 1:0.08. The use of PEG-200 and PEG-400 as solvent could activate the
Lewis Acid Catalyzed Ring‐Opening Reaction of Cyclobutanones towards Conjugated Enones
作者:Min Zhang、Jiqiang Gao、Jinbo Zhao、Tingtian Qiu、Zhongjuan Li、Ziteng Guo、Chunhui Liu、Yu Liu
DOI:10.1002/ejoc.202101335
日期:2021.12.7
An unprecedented Fe-catalyzed ring-opening reaction of simple cyclobutanones was disclosed. Such a novel approach givesaccess to substituted conjugate enones with good functional group tolerance in high yields under mild conditions.
Ligand‐free palladium‐catalyzed tandem pathways for the synthesis of 4,4‐diarylbutanones and 4,4‐diaryl‐3‐butenones under microwave conditions
作者:Anna Wirwis、Anna M. Trzeciak
DOI:10.1002/aoc.4870
日期:2019.5
Two efficient Pd‐catalyzed tandem pathways for the synthesis of 4,4‐diaryl‐2‐butanones and 4,4‐diaryl‐3‐buten‐2‐ones were elaborated. The first step in both procedures was the Heck coupling of methyl vinyl ketone (MVK) and various aryl iodides leading to 4‐aryl‐3‐buten‐2‐one with the yield of up to 92% in 1 hr. The second step performed with the same catalyst and a new portion of aryl iodide in the
阐述了两种有效的Pd催化串联途径,用于合成4,4-二芳基-2-丁酮和4,4-二芳基-3-丁二酮。两种方法的第一步都是甲基乙烯基酮(MVK)与各种芳基碘化物的Heck偶联反应,生成4-芳基-3-丁烯-2-酮,在1小时内产率高达92%。第二步是在K 2 CO 3为碱的情况下,使用相同的催化剂和新的一部分碘代芳基化物,以高收率生产4,4-二芳基-3-丁烯-2-酮。当使用叔胺代替K 2 CO 3时,反应选择性完全变为饱和的4,4-二芳基-2-丁酮,还原性的Heck产物。由于施加了微波辐射(MW),使用0.5 mol%的Pd(OAc)2催化剂而没有额外的配体,可以在短时间内(4小时)以高收率获得所需的产物。
Heck Reactions with Palladium Nanoparticles in Ionic Liquids: Coupling of Aryl Chlorides with Deactivated Olefins
Smooth operators: Heck reactions of aryl chlorides were catalyzed by ligand‐free palladium acetate in a molten mixture of tetraalkylammonium ionic liquids under aerobic and relatively mild conditions (see example). Deactivated electron‐rich aryl chlorides reacted with a wide array of substituted alkenes under these conditions, which thus enabled the coupling of combinations of substrates that are commonly