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1.
Reaction of N-tert-butyloxycarbonylasparagine (Boc-Asn) with 2 equiv of benzyl bromide in presence of cesium carbonate led to N-benzyl-3-Boc-amino-pyrrolidin-2,5-dione 1a (N-benzyl-3-Boc-aminosuccinimide). Borane dimethylsulfide reduced 3-Boc-aminopyrrolidine-2,5-dione 1a into 3-Boc-aminopyrrolidin-2-one 2a. The same procedure could also be used to prepare derivatives 1 and 2 substituted on the aromatic ring.  相似文献   
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Alkoxyphthalimides are prepared by alkylation of N-hydroxyphthalimide under solid-liquid phase transfer catalysis without solvent. When conversion of alkoxyphthalimides into alkoxylamines is nearly complete, neat hydrazine hydrate is added at room temperature.  相似文献   
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Regioselective hydrolysis of cocaine led, according to the reaction conditions, either to benzoylecgonine or to ecgonine methyl ester. Acylation with benzoylecgonine was readily achieved when benzotriazolyloxytrisdimethylamino-phosphonium (BOP) was used as a coupling agent.  相似文献   
4.
Solid-liquid PTC without added solvent efficiently promotes SNAr reactions of a variety of anionic nucleophiles generated in situ. This methodology is applied with success to some examples concerning non-activated aromatic systems. TDA-1 is the most effective catalyst.  相似文献   
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Solid-liquid phase transfer catalysis without added organic solvent efficiently promotes MICHAEL reactions. The method is applied here to the addition of acetylacetone, methylacetoacetate and fluorene anions on hindered acceptors.  相似文献   
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Solid-liquid phase transfer catalysis (PTC) without added solvent efficiently promotes Michael addition of substituted malonates on hindered acceptors. A rearrangement of adducts formed by addition of diethyl N-acetylaminomalonate is described.  相似文献   
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