Phenols were vinylated at the ortho-position with ethyne in the presence of SnCl(4)-Bu(3)N reagent. The reaction was applicable to phenols possessing either electron-donating or electron-withdrawing groups. 2,6-Divinylphenols were synthesized under modified conditions. A reaction mechanism involving carbostannylation of alkynyltin and phenoxytin was discussed.
Catalytic Ethenylation Reaction of Phenol Using SnCl<sub>4</sub>
作者:Katsumi Kobayashi、Masahiko Yamaguchi
DOI:10.1021/ol006888d
日期:2001.1.1
[figure: see text] Ethenylation reaction of phenol with silylethyne at the o-position is catalyzed by the SnCl4-BuLi reagent. While turn over numbers (TONs) in the reactions of m- or p-substitutedphenols are 3 to 4, those for o-substituted phenols are 8 to 9.
Phenols are 2,6-divinylated by treatment with ethyne at 100 °C in
chlorobenzene in the presence of SnCl
4
–Bu
3
N,
the divinylation occurring predominantly to exclusively with phenol,
alkylphenols and alkoxyphenols; an appropriate amount of the tin reagent
and the correct reaction temperature are essential for the
divinylation.
在 SnCl 4 -Bu 3 N 的存在下,在 100 °C 的氯苯中用乙炔处理苯酚,可使苯酚发生 2,6-二乙烯基化,二乙烯基化主要或完全发生在苯酚、烷基酚和烷氧基苯酚中;适量的锡试剂和正确的反应温度对二乙烯基化至关重要。