کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5225380 | 1383546 | 2007 | 8 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Arene-catalysed lithiation of phenyl- and 1,1-diphenylcyclopropane: synthetic applications Arene-catalysed lithiation of phenyl- and 1,1-diphenylcyclopropane: synthetic applications](/preview/png/5225380.png)
The reaction of phenylcyclopropane (1) with an excess of lithium and a catalytic amount of DTBB (2.5% molar) in THF at room temperature, followed by treatment with an electrophile [Me3SiCl, PhMe2SiCl, t-BuCHO, PhCHO, Me2CO, Et2CO, (CH2)5CO, adamantan-2-one, i-Pr2CO, di(cyclopropyl)ketone] and final hydrolysis with water leads to allylic products 10 or 11 depending on the structure of the electrophile: whereas for chlorosilanes or crowded ketones γ-products 11 are isolated, for aldehydes and non-congested ketones α-products 10 are formed. The application of the same protocol to 1,1-diphenylcyclopropane (7) leads to a mixture of products 13-15 resulting from the introduction of one or two electrophilic fragments to the open-chain mono- or dilithiated intermediate: also in this case the regiochemistry of the reaction is governed by steric reasons.
Journal: Tetrahedron - Volume 63, Issue 22, 28 May 2007, Pages 4655-4662