treatment with phenylselenyl chloride using ionic liquids as solvents/catalyzers has been developed. The reaction proceeds instantaneously under mild conditions with absolute regioselectivity, using primary, secondary, tertiary, and aromatic alcohols, as well as monosubstituted, disubstituted, and trisubstituted alkenols. This procedure provides a new method for the synthesis of substituted tetrahydrofurans
通过使用离子液体作为溶剂/催化剂,用苯硒基氯进行处理,开发了一种温和而有效的不饱和醇的氧硒环化方法。使用伯,仲,叔和芳族醇,以及单取代,二取代和三取代的烯醇,该反应在温和条件下以绝对的区域选择性瞬时进行。该方法为合成取代的四氢呋喃和四氢吡喃醚(许多具有生物活性的代谢物的前体)提供了一种新方法,从而避免了使用有毒和腐蚀性的催化剂。以前没有离子液体中硒介导的环功能化反应的报道。考虑到[MMIM] [MSO 4 ]的良好结果其易于制备,低粘度,低价格,可回收再利用的能力被选作溶剂/催化剂。量子化学计算(MP2(fc)/ 6-311 + G ** // B3LYP / 6-311 + G **)表明,分子内环化是由离子液体阴离子与羟基之间形成的氢键促进的组烯醇。
Kinetic and Mechanistic Studies of Base-Catalyzed Phenylselenoetherification of (<i>Z</i>)- and (<i>E</i>)-Hex-4-en-1-ols
作者:Vera M. Divac、Ralph Puchta、Zorica M. Bugarčić
DOI:10.1021/jp304314j
日期:2012.8.2
The mechanism of phenylselenoetherification of (Z)- and (E)-hex-4-en-1-ols using some bases (triethylamine, pyridine, quinoline, 2,2′-bipyridine) as catalysts and some solvents [tetrahydrofuran (THF) and CCl4] as reaction media was examined through studies of kinetics of the cyclization by UV–vis spectrophotometry. It was demonstrated that the intramolecular cyclization is facilitated in the presence
使用某些碱(三乙胺,吡啶,喹啉,2,2'-联吡啶)作为催化剂和某些溶剂[四氢呋喃(THF)]对(Z)-和(E)-hex-4-en-1-ols进行苯基硒醚化的机理和CCl 4通过紫外可见分光光度法研究环化动力学研究了作为反应介质的]。已经证明,由于碱和链烯醇的OH基团之间的氢键,在存在碱的情况下促进了分子内环化。碱催化反应中的速率常数受所用碱的庞大和碱性以及所考虑的氮供体的性质的影响很大。所获得的速率常数值表明与三乙胺的反应是最快的。具有更高极性和更高碱性的THF作为溶剂比CCl 4更好。量子化学计算[MP2(fc)/ 6-311 + G ** // B3LYP / 6-311 + G ** + ZPE(B3LYP / 6-311 + G **]表示(Z的环化)-hex-4-en-1-ol到四氢呋喃类五元环的动力学控制,而(E)-hex-4-en-1-ol到四氢吡喃类六元环的环化是热力学控制的。这与先前的实验结果一致。
Konstantinovic, Stanimir; Bugarcic, Zorica; Milosavljevic, Slobodan, Liebigs Annalen der Chemie, 1992, # 3, p. 261 - 268
Phenylselenoetherification and phenylselenolactonization were performed in one step by electrolysis of unsaturated alcohols or carboxylic acids and diphenyl diselenide in organic solvent containing halide ions as mediators.
Rapid SnCl2 catalyzed phenylselenoetherification of (Z)- and (E)-hex-4-en-1-ols
作者:Vera M. Divac、Marina D. Rvović、Zorica M. Bugarčić
DOI:10.1007/s00706-008-0936-y
日期:2008.11
A fast and efficient method for intramolecular heterocyclization of (Z)- and (E)-hex-4-en-1-ols was developed. The method does not cause side reactions of the substrates and provides the cyclic phenylselenoethers in high yields after only few minutes. A catalytic amount of SnCl(2) increased the yield, but in the presence of an equimolar amount of SnCl(2), formation of corresponding cyclic ethers were almost quantitative and reaction occurred instantaneously under extremely mild experimental conditions.