Rh(II)-catalyzed formal [3+3] cycloaddition of diazonaphthoquinones and propargyl alcohols: Synthesis of 2,3-dihydronaphtho-1,4-dioxin derivatives
作者:Mitsuru Kitamura、Tomoaki Nishimura、Kota Otsuka、Hirokazu Shimooka、Tatsuo Okauchi
DOI:10.1016/j.tetlet.2020.151853
日期:2020.5
A Rh(II)-catalyzed formal [3+3] cyclization of diazonaphthoquinones and propargyl alcohol is reported to afford 2,3-dihydro-1,4-benzodioxins. Various terminal propargyl alcohols react with diazonapthoquinone in the presence of Rh2(OAc)4 to give the corresponding dihydrodioxins in good to high yields. However, dihydrodioxins are not formed in the reaction of internal propargyl alcohols, and the O–H
据报道,Rh(II)催化的重氮萘醌和炔丙醇的正式[3 + 3]环化反应可提供2,3-二氢-1,4-苯并二恶英。各种末端炔丙醇在Rh 2(OAc)4的存在下与重氮萘醌反应,以高至高收率得到相应的二氢二恶英。但是,在内部炔丙醇的反应中不会形成二氢二恶英,取决于末端取代基,OH插入产物和2,5-二氢呋喃是主要产物。提出通过Rh(II)催化的分子间氧鎓叶立德形成和随后的内部炔基6- exo - dig环化反应形成2,3-二氢-1,4-苯并二恶英。