报道了铜催化下 α,β-不饱和砜的不同官能化。使用铜催化剂、磷酸烯丙酯、双(频哪醇)二硼和LiOMe实现了烯基砜的非对映选择性硼基化烯丙基化。在该方法中,将铜-硼基络合物添加到烯基砜中并随后进行烯丙基取代,使得硼烯丙基化产物具有良好的产率和优异的顺式非对映选择性。相反,更强的碱(KO t -Bu)通过消除磺酰基和硼基基团,进一步促进反应形成( E )-跳过的二烯。
Microwave-enhanced cross-coupling of allyl chlorides with vinyltrifluoroborates
作者:George W. Kabalka、Eric Dadush、Mohammad Al-Masum
DOI:10.1016/j.tetlet.2006.08.043
日期:2006.10
The allylation of potassium alkenyltrifluoroborates with allyl chloride via a palladiumcatalyzedcross-couplingreaction occurs rapidly undermicrowaveirradiation. The allylation reaction produces 1,4-pentadienes in high yields.
Allylic alcohols can be used directly for the palladium(0)-catalyzed allylation of aryl- and alkenylboronic acids with a wide variety of functional groups. A triphenylphosphine-ligated palladium catalyst turns out to be most effective for the cross-coupling reaction and its low loading (less than 1 mol%) leads to formation of the coupling product in high yield. The Lewis acidity of the organoboron
Oxime Palladacycle-Catalyzed Suzuki-Miyaura Alkenylation of Aryl, Heteroaryl, Benzyl, and Allyl Chlorides under Microwave Irradiation Conditions
作者:José F. Cívicos、Diego A. Alonso、Carmen Nájera
DOI:10.1002/adsc.201100019
日期:2011.7
cocatalyst, and potassium carbonate as base in N,N‐dimethylformamide at 130 °C under microwave irradiation conditions. Under these conditions, styrenes, stilbenes, and alkenylarenes are obtained in good to high yields, and with high regio‐ and diastereoselectivities in only 20 min. The reported protocol is also very efficient for the regioselective alkenylation of benzyl and allyl chlorides to afford allylarenes
The cross-couplingreaction of allylic carbonates with organosilanes was found to proceed without fluoride ion activation under mild conditions by using a coordinatively unsaturated palladium complex as a catalyst. The reaction was assumed to proceed through an allylpalladium alkoxide derived from the allylic carbonate substrate and a palladium(0) species, the alkoxo ligand activating the organosilicon
The title reaction is found to proceed in the presence of a palladium catalyst and in the absence of any activator. Various functional groups are tolerated to give a diverse range of 1,4-diene and diarylmethane products, which are ubiquitous units of natural products and pharmaceuticals.