我们在这里描述了一种替代和无过渡金属的程序,用于通过1,3-二炔的分子内环化作用与硒代苯酚稠合的苯并[ b ]硫属元素金属。这种有效的方法涉及双环化1,3-二炔硫属元素衍生物,这是通过在乙腈中使用Oxone®作为溶剂,通过二丁基二硒化物的Se-Se键的氧化裂解原位生成的有机硒的亲电子物种促进的在80°C下。在这项研究中,制备了15种具有广泛底物范围的硒代苯酚,收率中等至极好(55-98%),反应时间短(0.5-3.0 h)。
p-Toluenesulfonic acid-promoted selective functionalization of unsymmetrical arylalkynes: a regioselective access to various arylketones and heterocycles
Regioselective hydration of a wide range of internalalkynes has been afforded in high to good yields by using PTSA in EtOH. The scope of the reaction of alkynes has been delineated. Arylaliphatic alkynes and diarylalkynes were regioselectively hydrated in good to excellent yields and short reaction times when the reaction was achieved under microwave irradiation. Moreover, diarylalkynes, arylenynes
Synthesis of benzo[<i>b</i>]chalcogenophenes fused to selenophenes <i>via</i> intramolecular electrophilic cyclization of 1,3-diynes
作者:Paola S. Hellwig、Jonatan S. Guedes、Angelita M. Barcellos、Raquel G. Jacob、Claudio C. Silveira、Eder J. Lenardão、Gelson Perin
DOI:10.1039/d0ob02362k
日期:——
We describe herein an alternative and transition-metal-free procedure for the access of benzo[b]chalcogenophenes fused to selenophenes via intramolecular cyclization of 1,3-diynes. This efficient protocol involves a double cyclization of 1,3-diynyl chalcogen derivatives promoted by the electrophilic species of organoselenium generated in situ by the oxidative cleavage of the Se–Se bond of dibutyl diselenide
我们在这里描述了一种替代和无过渡金属的程序,用于通过1,3-二炔的分子内环化作用与硒代苯酚稠合的苯并[ b ]硫属元素金属。这种有效的方法涉及双环化1,3-二炔硫属元素衍生物,这是通过在乙腈中使用Oxone®作为溶剂,通过二丁基二硒化物的Se-Se键的氧化裂解原位生成的有机硒的亲电子物种促进的在80°C下。在这项研究中,制备了15种具有广泛底物范围的硒代苯酚,收率中等至极好(55-98%),反应时间短(0.5-3.0 h)。
MPHT-Promoted Bromocyclization of ortho-Substituted Arylalkynes: Application to the Synthesis of 2-Substituted 3-Bromobenzofurans and -Benzo[b]thiophenes
A convenient and general approach to the synthesis of 2‐substituted 3‐bromobenzofurans and ‐benzothiophenes was developed. The procedure is based on the cyclization of ortho‐substituted arylalkynes in the presence of N‐methylpyrrolidin‐2‐one hydrotribromide (MPHT) as a soft and easy‐to‐handle electrophilic brominating reagent. Under mild reaction conditions, MPHT promoted the bromocyclization of various