Brønsted Acid Catalyzed Functionalization of Aromatic Alcohols through Nucleophilic Substitution of Hydroxyl Group
作者:Abhishek Kumar Mishra、Srijit Biswas
DOI:10.1021/acs.joc.5b02849
日期:2016.3.18
have been substituted by O-, S-, N-, and C-centered nucleophiles under solvent-free reaction conditions. The products are generated in good to excellent yields. para-Toluenesulfonic acid exhibits the best catalytic activity compared to other Brønstedacids. Experimental observations suggest that the reaction proceeds through the intermediacy of the keto tautomer of naphthol. Nucleophilic addition to
在无溶剂反应条件下,萘酚和互变异构酚衍生物的羟基已被O-,S-,N-和C中心的亲核试剂取代。产生的产品良率极佳。与其他布朗斯台德酸相比,对甲苯磺酸显示出最佳的催化活性。实验观察表明该反应通过萘酚的酮互变异构体的中间体进行。亲核加成到羰基上,然后除去水,得到所需产物。本方法提供了对取代的萘[2,1- b ]呋喃衍生物的访问。使用N生成的产品以中心为中心的亲核试剂可以进一步转化为重要种类的有机分子,例如苯并咔唑和咪唑衍生物。
One-Step Regioselective Synthesis of Benzofurans from Phenols and α-Haloketones
Reported here is the direct synthesis of naphthofurans and benzofurans from readily available phenols and α-haloketones promoted by titanium tetrachloride which combines Friedel–Crafts-like alkylation and intramolecular cyclodehydration into one step. This simple protocol allows for the formation of a variety of high value naphthofurans and benzofurans within which a series of cyclic and acyclic groups
Novel cis- and trans-(o-H/Me/vinyl) substituted styryl furo-benzobicyclo[3.2.1]octadiene derivatives (7a,b, 8) were prepared and transformed to the novel naphthofuran derivatives of benzobicyclo[3.2.1]octadiene (6a,b) and novel phenanthrene-benzobicyclo[3.2.1]octadiene derivative (11) by photochemical electrocyclic ring closure in the presence of iodine and by intramolecular photoinduced [4+2] cycloaddition
新颖顺-和反式- (ø -H / ME /乙烯基)取代苯乙烯基呋喃并-benzobicyclo [3.2.1]辛二烯衍生物(图7a,b,8)中制备,并转化到benzobicyclo的新颖naphthofuran衍生物[3.2.1]碘存在下,通过光化学电环闭合和分子内光诱导的[4 + 2]环加成反应分别生成辛二烯(6a,b)和新型菲-苯并双环[3.2.1]辛二烯衍生物(11)。这些新型的退火双环[3.2.1]辛二烯衍生物(6a,b,11)尤其有趣的是,它们在定义的几何排列方式下以两个芳香单元的刚性甲醇桥联结出现,因此成为分子夹的潜力。