128947-02-4Relevant articles and documents
N-Alkenoylimidazolidin-2-ones as chiral dienophiles in Diels-Alder cycloaddition reactions
Roos, Gregory H. P.,Kriel, Karina N.,Emslie, Neville D.,Balasubramaniam, Sundari
, p. 104 - 112 (2007/10/03)
Homochiral N-enoylimidazolidin-2-ones 5-8 are readily accessible, practical, and highly diastereoselective dienophiles in dialkylaluminium-promoted Diels-Alder reactions. Acrylate, methacrylate, and (E)-crotonate derivatives bearing ephedrine-based imidaz
Asymmetric synthesis of syn hydroxyphenylalanine via aziridine ring expansion to an oxazoline
Cardillo, Giuliana,Gentilucci, Luca,Tolomelli, Alessandra
, p. 8261 - 8264 (2007/10/03)
The synthesis of (2R,3S)- and (2S,3R)-hydroxyphenylalanine is reported. The main steps are the 1,4-addition of O-benzylhydroxylamine to unsaturated imides and the ring expansion of trans-aziridines.
A novel method for the N-acylation of (4R,5S)-1,5-dimethyl-4-phenylimidazolidin-2-one
Kriel, Karina N.,Emslie, Neville D.,Roost, Gregory H. P.
, p. 109 - 110 (2007/10/03)
An efficient synthesis of N-Acylimidazolidinones derived from α,β-unsaturated acid chlorides using DABCO as the base is described.
Dibutylboron triflate promoted conjugate addition of benzylic and allylic organocopper reagents to chiral α,β-unsaturated N-acyl imidazolidinones
Van Heerden, Pieter S.,Bezuidenhoudt, Barend C.B.,Ferreira, Daneel
, p. 1821 - 1824 (2007/10/03)
The organocopper-Lewis acid system, RCu-TMEDA-Bu2BOTf, is useful for conjugate addition to highly constrained chiral α,β-unsaturated N-acyl imidazolidinones. In comparison with the corresponding TMSCl-activated reagents, Bu2BOTf exhi
Synthesis of enantiomerically pure trans aziridine-2-carboxylates by diastereoselective Gabriel-Cromwell reaction
Cardillo, Giuliana,Gentilucci, Luca,Tomasini, Claudia,Castejon-Bordas, Maria Pilar Visa
, p. 755 - 762 (2007/10/03)
Benzyl aziridine-2-carboxylates have been obtained in high yield and selectivity by conjugate addition of ammonia to α,β-unsaturated chiral imides followed by treatment with lithium benzyloxide. A ring-expansion of the aziridine to an oxazoline allowed th
Asymmetric 1,4-addition of Grignard reagents to chiral α,β-unsaturated imides in the presence of Lewis acids
Bongini,Cardillo,Mingardi,Tomasini
, p. 1457 - 1466 (2007/10/03)
The asymmetric 1,4 addition of PhMgCl, MeMgBr and allylMgBr to chiral imides 1 has been studied under various conditions. The presence of a Lewis acid, as AlMe2Cl, affords an enhanced diastereoselectivity favouring the formation of the product derived from the attack on the re face. The 1,4 addition of allyl diisopropoxyborate to imides 1 has also been analysed.
Diastereoselective additions of alkyl, akenyl, aryl and allyl cuprates to unsaturated chiral imides
Melnyk,Stephan,Pourcelot,Cresson
, p. 841 - 850 (2007/10/02)
Some diastereoselective conjugate additions of cuprates to chiral unsaturated imides bearing an imidazolidinyl group (from ephedrine and urea) show an impressive stereoselectivity. The chiral (internal auxiliary dependent) group is easily broken and recyc