Alkylative Dearomatization by Using an Unactivated Aryl Nitro Group as a Leaving Group: Access to Diversified Alkylated Spiro[5.5]trienones
作者:Dong Xia、Xin-Fang Duan
DOI:10.1021/acs.orglett.1c00469
日期:2021.4.2
cleavage of an unactivated aryl nitro group triggered by alkyl radicals enables a dearomative cyclization, affording diversified alkylated spiro[5.5]trienones in good yields. Using readily available compounds (toluene and analogues, alkanes, ethers, ketones, etc.) as alkylating reagents, various alkyls have been implanted into the spirocycles via C(sp3)–H and Ar–NO2 bondactivation with high functional
DTBP‐Mediated Cascade Spirocyclization and Dearomatization of Biaryl Ynones: Facile Access to Spiro[5.5]trienones through C(sp
<sup>3</sup>
)−H Bond Functionalization
作者:Ming‐Ming Zhang、Liu‐Yu Shen、Sa Dong、Bing Li、Fei Meng、Wei‐Jie Si、Wen‐Chao Yang
DOI:10.1002/ejoc.202100656
日期:2021.8.20
A novel DTBP-promoted metal-free cascade cyclization of biary ynones with a variety of hydrocarbons including toluenes, ethers, ketones and alkanes has been established, which provides an expeditious approach to access functionalized spiro[5.5]trienones in moderate to good yields. The products thus obtained represent key structural motifs of biologically active molecules in pesticide.
Electrochemical Trifluoromethylthiolation and Spirocyclization of Alkynes with AgSCF<sub>3</sub>: Access to SCF<sub>3</sub>-Containing Spiro[5,5]trienones
作者:Wen-Chao Yang、Ming-Ming Zhang、Yu Sun、Cai-Yun Chen、Lei Wang
DOI:10.1021/acs.orglett.1c02260
日期:2021.9.3
efficient strategy for trifluoromethylthiolation and dearomatization of activated alkynes with stable and readily available AgSCF3 has been developed. Reported herein is the unprecedented electrochemical generation of the SCF3 radical in the absence of persulfate for the synthesis of SCF3-containing spiro[5,5]trienones in good yields via a 6-exo-trig radical cyclization.
Iron-Catalyzed Dearomatization of Biaryl Ynones with Aldehydes via Double C–H Functionalization in Eco-Benign Solvents: Highly Atom-Economical Synthesis of Acylated Spiro[5.5]trienones
作者:Dong Xia、Xin-Fang Duan
DOI:10.1021/acs.joc.1c01870
日期:2021.11.5
bonds of biaryl ynones render the 6-exo-trig regioselective C–H activation dearomatization to spiro[5.5]trienones challenging since the competing reactions of C–H bonds on Ar1 or the ortho-C–H bonds on Ar3 may result in 5-exo-trig cyclization to indenones or 6-exo-trig ortho-dearomatization, respectively. We here report an unprecendented dearomatization of biaryl ynones with aldehydes via double C–H
iodine)-induced intramolecular 7-endo-dig cyclization of 1-([1,1′-biphenyl]-2-yl)alkynones is reported. Detailed investigations on the substituenteffectsduring the electrophilic iodocyclization of the alkynones show that they play a crucial role in determining the reaction pathways of the cyclization. By modifying the substitution pattern on the alkynone substrates, the cyclization takes place regioselectively