We have developed a photochemical ATRA/ATRC reaction that is mediated by halogen bonding interactions. This reaction is caused by the reaction of malonic acid ester derivatives containing bromine or iodine with unsaturated compounds such as alkenes and alkynes in the presence of diisopropylethylamine under visible light irradiation. As a result of various control experiments, it was found that the
α-bromocarbonyls for the synthesis of various cyclohexenone-fused polycyclic compounds is described. Up to six new C–C bonds and four new carbocycles can be established in a single reaction, highlighting the high efficiency and step-economics of this protocol. This reaction offers a novel and straightforward entry to the synthesis of ketones featuring the addition of carbon radicals to aldehydes.
addition/cyclization/halogen atomtransferbetween alkynes and α-halogeno-γ, δ-unsaturated carbonyl compounds for the synthesis of various substituted cyclopentenes is described. Since up to four Csp3–Csp2 bonds, two Csp3–Br bonds, and two carbocycles can be established in a single reaction, this 100% atom-efficient reaction exhibits the advantages of wide substrate scope, high functional group tolerance, and step-economics
A photosensitizer-free, highly efficient sunlight-promoted tandem [3+2]/[4+2] annulation of unsaturated α-bromocarbonyls with o-alkynylanilines was developed, and allowed for convenient synthesis of fused benzobicyclic skeletons. The reaction was clean and practical in mild conditions and showed excellent functional group compatibility.
Visible-Light-Promoted Cascade Cyclization of 3-Ethynyl-[1,1′-biphenyl]-2-Carbonitriles with Unsaturated α-Bromocarbonyls
作者:Yu-Song Ran、Bo Jiang、Yun-Tao Shen、Tai-Gang Fan、Wei Jiang、Cui Zhang、Ya-Min Li
DOI:10.1021/acs.orglett.3c02938
日期:2023.10.13
1′-biphenyl]-2-carbonitriles with unsaturated α-bromocarbonyls for the synthesis of tetrahydrobenzo[mn]cyclopenta[b]acridines is described. Three C(sp3)–C(sp2) bonds, one C(sp2)–N bond, and three cycles can be formed in a single reaction through the addition of a C-centered radical to the carbon–carbon triple bond and three radical cyclizations. This reaction features mild conditions, wide substrate scope, and high