环外丙二烯天然产物和药物是稀有但有趣的化合物:褐藻黄质,蚱酮和前列环素,头孢菌素,抗血栓剂和固醇生物合成抑制剂的类似物是代表性的。环外烯丙基的合成通常依赖于扩展的共轭加成,例如,alk-2-en-4-ynones,syn S N炔基肟基的2'样加成,以及炔丙基硅烷的亲电取代等取代反应。我们报告说3-炔基-2-环烯酮与2当量的各种氢铝酸盐而不是氢硼酸盐的反应是通过非对映选择性的1,4-还原乙烯基炔丙基中间体醇盐进行的,以提供环外烯丙基为主要产物。还观察到异构的3-炔基环烷醇。
Carbonyl transposition on organoselenium compounds
作者:João V. Comasseto、Wai L. Lo、Nicola Petragnani
DOI:10.1016/s0040-4020(97)00454-7
日期:1997.6
Carbonyl conjugated vinylic selenides undergo 1,3 and 1,5-carbonyl transposition sequences through organometallic reagents addition reactions followed by acid hydrolysis.
Palladium(II)-catalyzed coupling of 2-carboxyethyl enol triflates with organostannanes.
作者:Ioannis N. Houpis
DOI:10.1016/s0040-4039(00)93572-x
日期:1991.11
Enol triflates 1–5, derived from the corresponding dicarbonyl compound, were coupled with tin reagents 6–8 using Pd(OAc)2 and PPh3 as the catalyst, at 7 mole %, in 56–91% yield.
enones present as s-trans conformers to provide good yields of the silyl enol ethers of beta-acetylido carbonyl compounds. Typically good substrates are 2-cyclopentenone, 2-cyclohexenone, alpha,beta-unsaturatedaldehydes, and beta-alkoxy-alpha-enones. Copper acetylide reagents prepared from CuI and an alkynyllithium give considerably higher yields than those prepared from CuBr or CuCN. Iodotrimethylsilane
Palladium-Catalyzed Decarboxylative Coupling of Alkynyl Carboxylic Acids and Alkenyl Tosylates for the Synthesis of Enynones
作者:Subeen Yu、Eunjeong Cho、Jimin Kim、Sunwoo Lee
DOI:10.1021/acs.joc.7b02175
日期:2017.10.20
A palladium-catalyzed decarboxylativecoupling reaction was developed for the synthesis of 3-(1-alkynyl)-2-cyclohexen-1-ones. A variety of alkynyl carboxylic acids were coupled with 3-oxocyclohexenyl tosylates to afford the corresponding enynones in good to excellent yields. The developed catalytic system is phosphine free and showed good tolerance toward various functionalities such as chloride, cyano
regioselectivity with respect to copper-catalyzedconjugateadditions of various Grignard reagents to cyclic enynones. The use of Cu(OTf)2 and NHC ligand L1 as the catalyst combination in CH2Cl2 led to the unique formation of the 1,4 adduct. This selectivity does not follow the general trend previously observed in the literature using extended Michael acceptors. Moreover these reactions allowed for the creation