Search results for "Protecting group"

ChemInform Abstract: The (2-Phenyl-2-trimethylsilyl)ethoxycarbonyl (Psoc) Group - A Novel Amino Protecting Group.

2001

ChemInform Abstract: Syntheses of Polyfunctionalized Resveratrol Derivatives Using Wittig and Heck Protocols.

2012

In the modified Wittig reaction, Tms is used as a highly valuable protecting group of the phenolic functions of the starting arenes.

ChemInform Abstract: Boron Aldol Additions with Erythrulose Derivatives: Dependence of Stereoselectivity on the Type of Protecting Group.

2010

Abstract Boron aldol additions of 1- O -silylated 3,4-di- O -benzyl- and 3,4-di- O -benzoyl- l -erythrulose and achiral aldehydes using dicyclohexylboron chloride have been investigated. The dibenzyl derivative gave syn/syn stereoisomers with high stereoselectivity, whereas the dibenzoyl derivative gave syn/anti stereoisomers. It is believed that, while the dibenzoyl erythrulose gives rise to the E enolate in the presence of dicyclohexylboron chloride, as usually observed with this reagent, only the Z enolate is formed in the case of the dibenzyl derivative.

(2-Pyridyl)sulfonyl Groups for ortho -Directing Palladium- Catalyzed Carbon-Halogen Bond Formation at Functionalized Arenes

2017

International audience; We describe an efficient palladium-catalyzed selective C-H ortho-monohalogenation (X=I, Br, Cl, F) of various functionalized (2-pyridyl) aryl-sulfones. ortho-, meta-and para-functionalization is tolerated at the arene group which undergoes C-H halogenation. Some modifications are also possible on the 2-(arylsulfonyl) heteroaryl directing groups. A comparison of the halogenation efficiency suggests that bromination is the practical method of choice, while chlorination and fluorination are possible but more challenging. Under forcing conditions ortho-dihalogenation can also be achieved.