<b>
Synthesis of Acrylonitriles
<i>via</i>
Mild Base Promoted Tandem Nucleophilic
<scp>Substitution‐Isomerization</scp>
of
<scp>α‐Cyanohydrin</scp>
Methanesulfonates
</b>
作者:Shiwen Liu、Lingling Meng、Xiaojun Zeng、Gerald B. Hammond、Bo Xu
DOI:10.1002/cjoc.202000579
日期:2021.4
Main observation and conclusion We have developed an efficient synthesis of acrylonitriles via mild base promoted tandem nucleophilic substitution‐isomerization of α‐cyanohydrin methanesulfonates with alkenylboronic acids. This transition metal‐free protocol works under simple and mild conditions and offers good chemical yields for a wide range of substrates and demonstrates good functional group tolerance
Direct alkenylation of a variety of alcohols with vinylboronicacids has been accomplished using the air‐stable calcium(II) complex Ca(NTf2)2 under mild conditions with short reaction times. For reluctant transformations, an ammonium salt was used as an additive to circumvent the reactivity issue.
Palladium-Catalyzed Cross-Coupling of <i>N</i>-Sulfonylaziridines and Alkenylboronic Acids: Stereospecific Synthesis of Homoallylic Amines with Di- and Trisubstituted Alkenes
作者:Wei Pin Teh、Forrest E. Michael
DOI:10.1021/acs.orglett.7b00504
日期:2017.4.7
palladium-catalyzed cross-coupling of 2-alkylaziridines with alkenylboronic acids to give homoallylamines is presented. The reaction is highly regioselective and stereospecific and provides convenient access to enantioenriched amines with 1,1-disubstituted, 1,2-disubstituted, and trisubstituted alkenes. The modular synthesis of a 2,5-disubstituted pyrrolidine natural product was completed in three steps
Deaminative metal-free reaction of alkenylboronic acids, sodium metabisulfite and Katritzky salts
作者:Tonghao Zhu、Jia Shen、Yuyuan Sun、Jie Wu
DOI:10.1039/d0cc07632e
日期:——
observed and sodium metabisulfite is used as the source of sulfur dioxide. Mechanistic studies show that the alkyl radical generated in situ from Katritzky salt via a single electron transfer with alkenylboronic acid or DIPEA is the key step for providing an alkyl radical intermediate, which undergoes further alkylsulfonylation with sulfur dioxide.
of 2‐vinyl nitrogen‐containing heteroaromatic compounds with styrylboronicacid in the presence of a cobalt catalyst and a base results in an addition reaction to afford the corresponding 4‐phenyl‐3‐butenyl heteroarenes. The adjacent nitrogen atom is essential for the promotion of the reaction because the nitrogen accelerates the addition of the styryl cobalt species, generated by transmetalation, onto