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.