2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) was found to be a very efficient oxidativereagent for the selective cleavage of tosylhydrazones and oximes of carbonyl compounds for the first time.
Wittig Ylide Mediated Decomposition of <i>N</i>-Sulfonylhydrazones to Sulfinates
作者:Deepika Choudhary、Vineeta Khatri、Ashok K. Basak
DOI:10.1021/acs.orglett.7b03953
日期:2018.4.6
N-Sulfonylhydrazones generate sulfinates selectively when treated with a stabilized Wittig ylide in a polar aprotic solvent at elevated temperature. The transition metal and base free decomposition method is applicable to N-sulfonylhydrazones generated from a number of aromatic and heteroaromatic aldehydes and ketones. In the case of N-tosylhydrazones derived from O-allyl and O-propargyl salicylaldehydes
The reaction of the p-tolyl(or phenyl)sulfonylhydrazones of some 2-(alkenyloxy)benzaldehydes with lead tetraacetate leads, via the nitrile imide intermediates, Ar–\overset+C=N–\overset−N–SO2–C6H4–X-p, to intramolecular 1,3-dipolar cycloadducts and 1-acetyl-2-aroyl-1-[p-tolyl(or phenyl)sulfonyl]hydrazines in 20–65% and 7–70% yields respectively, while the intermolecular reactions of the benzaldehyde
Synthesis of Phenanthrenes through Copper-Catalyzed Cross-Coupling of <i>N</i>-Tosylhydrazones with Terminal Alkynes
作者:Mohammad Lokman Hossain、Fei Ye、Zhenxing Liu、Ying Xia、Yi Shi、Lei Zhou、Yan Zhang、Jianbo Wang
DOI:10.1021/jo501489c
日期:2014.9.19
for the synthesis of phenanthrenes through the copper-catalyzed reaction of aromatic tosylhydrazones with terminalalkynes is explored. The reaction proceeds via the formation of an allene intermediate and subsequent six-π-electron cyclization–isomerization, affording phenanthrene derivatives in good yields. The transformation can be performed in two ways: (1) with N-tosylhydrazones derived from [1,1
CuI-Catalyzed Cross-Coupling of <i>N</i>-Tosylhydrazones with Terminal Alkynes: Synthesis of 1,3-Disubstituted Allenes
作者:Mohammad Lokman Hossain、Fei Ye、Yan Zhang、Jianbo Wang
DOI:10.1021/jo3024686
日期:2013.2.1
A CuI-catalyzedsynthesis of 1,3-disubstituted allenesfrom1-alkynes by the reaction with various N-tosylhydrazones has been developed. This method, which uses readily available starting materials and is operationally simple, offers 1,3-disubstituted allenes in moderate to good yields. The reaction also tolerates various functional groups.