Addition reaction of arylboronic acids to aldehydes and α,β-unsaturated carbonyl compounds catalyzed by conventional palladium complexes in the presence of chloroform
作者:Tetsuya Yamamoto、Michiko Iizuka、Hiroto Takenaka、Tetsuo Ohta、Yoshihiko Ito
DOI:10.1016/j.jorganchem.2008.12.032
日期:2009.4
Arylboronic acids react with aldehydes and α,β-unsaturatedcarbonylcompounds in the presence of a base and a catalytic amount of a palladium(0) complex with chloroform, affording the corresponding addition products in good yields, and chiral benzhydrol was obtained with up to 43% e.e. using (S,S)-bppm as a ligand. General palladium complexes have no catalytic activity without chloroform. Because chloroform
Visible-Light-Triggered C–C and C–N Bond Formation by C–S Bond Cleavage of Benzylic Thioethers
作者:Matteo Lanzi、Jérémy Merad、Dina V. Boyarskaya、Giovanni Maestri、Clémence Allain、Géraldine Masson
DOI:10.1021/acs.orglett.8b02196
日期:2018.9.7
The cleavage of sulfidic C–S bonds under visible-light irradiation was harnessed to generate carbocations under neutral conditions and synthesize valuable di- and triarylalkanes as well as benzyl amines. To this end, photoredox catalysis and direct photoinduced C–S bondcleavage are used as complementary approaches and participate in the versatility of the general strategy. Extensive mechanistic studies
The cooperative effect of Lewis pairs in the Friedel–Crafts hydroxyalkylation reaction: a simple and effective route for the synthesis of (±)-carbinoxamine
An efficient C–C bond formation strategy between aromatic/heteroaromatic π-nucleophiles and Lewis acid activated aldehydes is described. This aromatic electrophilic substitution reaction of arenes or heteroarenes is facilitated by Lewis acid AlBr3. Aromatic rings with electron donating substituents are excellent nucleophilic counterparts in this reaction, generating carbinols in excellent yields (61–94%)
An unprecedented dehydrative C–C bond formation between unprotected anilines with benzyl alcohols is disclosed. Re2O7 catalyst (5 mol %) at elevated reaction temperature (80 °C) provided C-benzylanilines with high to excellent yields and with good chemoselectivities (over N-alkylation). A probable mechanism has been proposed based on mechanistic studies.
The isomerisation of α- and β-benzyl- and substituted-benzyl-naphthalenes catalysed by anhydrous aluminium chloride or toluene-p-sulphonic acid has been studied.