Reaction of the N-(α-chloroalkyloxycarbonyl)pyrrolidines 1 with lithium powder and a catalytic amount of 4,4′-di-tert-butylbiphenyl (DTBB, 2.5 mol-%) in the presence of different electrophiles [iBuCHO, tBuCHO, PhCHO, Et2CO, (CH2)5CO, PhCOMe, Ph2CO, Me3SiCl], in THF at temperatures ranging between –78 and –60°C leads, after hydrolysis with water, to the expected functionalized carbamates 2. Deprotection
To improve the synthesis and reactivity of phthaloylperoxide derivatives a method has been developed using sodium percarbonate and phthaloyl chlorides. The reactions of the new phthaloylperoxide derivatives with trans-stillbene as well as the improved reactivity of 3,4-dichlorophthaloyl peroxide with a variety of alkenes are reported.
Opportunities for insiders: A catalytic pinacol-type reductiverearrangement of 1,2-internal diols was developed by the use of a simple boron catalyst and two silanes (see scheme). The reaction occurs through a concerted, stereoinvertive mechanism and is applicable to several substrate scaffolds not usually amenable to pinacol-type reactions, such as aliphatic secondary–secondary diols, without the
Processes for Highly Enantio- and Diastereoselective Synthesis of Acyclic Epoxy Alcohols and Allylic Epoxy Alcohols
申请人:Walsh Patrick
公开号:US20090163728A1
公开(公告)日:2009-06-25
The inventive subject matter relates to novel processes for making an epoxy alcohol from an aldehyde, comprising the steps of: (a) adding (i) an organozinc compound or (ii) divinylzinc compound and an diorganozinc compound to said aldehyde in the presence of a first catalyst to form an allylic alkoxide compound; and (b) epoxidizing said allylic alkoxide compound in the presence of an oxidant and a second catalyst.
Process for the preparation of (meth)acrylate esters and polyester (meth)acrylates
申请人:UCB, S.A.
公开号:EP0992480A1
公开(公告)日:2000-04-12
An improved process for preparing acrylate esters, methacrylate esters, polyester acrylates or polyester methacrylates by reacting acrylic or methacrylic acid with a monohydroxy containing compound or a polyhydroxy containing compound in the presence of a catalyst and polymerization inhibitor in a reaction vessel, in the presence or absence of a solvent, under microwave energy as a heating source. Advantages of using microwave energy in place of conventional thermal heating include higher temperatures coupled with shorter residence times, reduced production costs, increased capacity, lower energy costs, effective use of raw materials, and solventless processing which is environmentally friendly.