Highly Efficient Synthesis of Multi-Substituted Allenes from Propargyl Acetates and Organoaluminum Reagents Mediated by Palladium
作者:Qinghan Li、Zhen Zhang、Xuebei Shao、Gang Zhang、Xinying Li
DOI:10.1055/s-0036-1588177
日期:2017.8
The process was simple and easily performed, which offers an efficient method to synthesize the multi-substituted allene derivatives. A simple and mild catalytic SN2′ substitution reaction of propargylacetates with organoaluminum reagents is reported. The SN2′ substitution reaction of propargylacetates with organoaluminum reagentsmediated by Pd(PhP3)2Cl2 (1 mol%)/PPh3 (2 mol%)/K2CO3 in tetrahydrofuran
摘要 一种简单和温和的催化小号Ñ报道与有机铝试剂炔丙基乙酸酯的2'取代反应。Pd(PhP 3)2 Cl 2(1 mol%)/ PPh 3(2 mol%)/ K 2 CO 3在四氢呋喃中于60°C介导的乙酸丙炔酯与有机铝试剂的S N 2'取代反应3– 4小时以高产率(高达99%)以良好的产率(高达94%)提供了相应的多取代的烯。该方法简单易行,为合成多取代的丙二烯衍生物提供了一种有效的方法。 一种简单和温和的催化小号Ñ报道与有机铝试剂炔丙基乙酸酯的2'取代反应。Pd(PhP 3)2 Cl 2(1 mol%)/ PPh 3(2 mol%)/ K 2 CO 3在四氢呋喃中于60°C介导的乙酸丙炔酯与有机铝试剂的S N 2'取代反应3– 4小时以高产率(高达99%)以良好的产率(高达94%)提供了相应的多取代的烯。该方法简单易行,为合成多取代的丙二烯衍生物提供了一种有效的方法。
Direct Transformation of Silyl Enol Ethers into Functionalized Allenes
The first elimination reactions of silyl enol ethers to lithiated allenes are reported. These reactions allow a direct transformation of readily available silyl enol ethers into functionalized allenes. The action of three to four equivalents of lithium diisopropylamide (LDA) on silyl enol ethers results in the formation of lithiated allenes by initial allylic lithiation, subsequent elimination of a lithium
Treatment of 1,1-dichloroalk-1-enes with Cp2Ti[P(OEt)3]2 produced organotitanium species, which afford allenes on treatment with aldehydes and ketones.
用Cp2Ti[P(OEt)3]2处理1,1-二氯烯烃,生成有机钛物种,与醛和酮反应生成烯烃。
Propargylic Dithioacetal as an Allene 1,3-Dication Synthon. Nickel-Catalyzed Cross-Coupling Reactions of Propargylic Dithioacetals with Grignard Reagents
作者:Hsian-Rong Tseng、Tien-Yau Luh
DOI:10.1021/jo961514c
日期:1996.1.1
Palladium-catalyzed, ligand-free S N 2’ substitution reactions of organoaluminum with propargyl acetates for the synthesis of multi-substituted allenes
作者:Xuebei Shao、Chang Wen、Gang Zhang、Kangping Cao、Ling Wu、Qinghan Li
DOI:10.1016/j.jorganchem.2018.06.020
日期:2018.9
We describe a convenient method for the synthesis of multi-substituted allenes from SN2′ substitution reactions organoaluminum with propargyl acetates: The SN2′ substitution reaction of organoaluminum (0.4 mmol) with propargyl acetates (0.5 mmol) mediated by PdCl2(dppf) (1 mol%) at 60 °C in THF without ligand could produce multi-substituted allenes in moderate to good yields (up to 98%) and high selectivities