X=Y-ZH systems as potential 1,3-dipoles. Part 32 generation of nitrones from oximes. Tandem Michael addition-1,3-dipolar cycloaddition reactions. Background and class 1 processes.
作者:Ronald Grigg、Frances Heaney、Sivagnanasundram Surendrakumar、William J. Warnock
DOI:10.1016/s0040-4020(01)87116-7
日期:1991.1
keto nitrones can be trapped in regiospecific intermolecular cycloadditionreactions giving single cycloadducts in good yield. Chemospecific 1:1:1 cycloadducts are obtained from ketoximes, monosubstituted electronegative olefins (Michael acceptor) and N-methylmaleimide (dipolarophile), whilst the chemoselectivity of the corresponding reactions with aldoximes is dependent on the oxime stereochemistry.
A green chemical approach for the N-alkylation of aldoximes to form nitrones in organized aqueous media and their in situcycloaddition with olefins
作者:Sandip K. Hota、Amrita Chatterjee、Pranab K. Bhattacharya、Partha Chattopadhyay
DOI:10.1039/b812290c
日期:——
Aldoximes react with α,β-unsaturated carbonyl and sulfonyl compounds in organized aqueous media (nanoreactor system) using dodecylbenzenesulfonic acid (DBSA) as surfactant to generate N-alkylated nitrones, which undergo intermolecular cycloaddition in the same pot with maleimides to give the desired cycloadduct in absence of any organic solvent and catalyst. Divinyl sulfone was successfully used for both N-alkylation and intramolecular cycloaddition, affording only one cycloadduct. This is a new example of green chemistry and provides a new aspect of reactions in water.