Regioselective introduction of functional groups in α-diimines by means of dialkylzinc compounds. Synthesis of functionalized 2- and 3-pyrrolidinone derivatives
作者:Elmo Wissing、Henk Kleijn、Jaap Boersma、Gerard van Koten
DOI:10.1002/recl.19931121203
日期:——
(t-BuDAB) by functionally substituted diorganozinc compounds Zn[(CHR1XCH2)nXR2]2 (n = 1–3, R1 = H, Me, XR2 = OMe, OBn, SEt, NMe2, COOEt) occurs regioselectively. Alkylation occurs at the nitrogen atom of the N=C-C=N skeleton of t-BuDAB when primary diorganozinc compounds are used (R1 = H), but at the carbon atom when secondary and benzylic diorganozinc compounds are employed. The functional groups in the
的烷基化1,4-二氮杂-1,3-丁二烯吨-BuN = CH-CH = N吨-Bu(吨-BuDAB)通过官能取代diorganozinc化合物的Zn [(CHR 1 XCH 2)Ñ XR 2 ] 2(n = 1-3,R 1 = H,Me,XR 2 = OMe,OBn,SEt,NMe 2,COOEt)区域选择性地发生。当使用伯二有机锌化合物时,烷基化发生在t -BuDAB的N = CC = N骨架的氮原子上(R 1= H),但是当使用仲和苄基二有机锌化合物时在碳原子上。仅在Zn [(CH 2)3 NMe 2 ] 2(7)和Zn(C 6 H 4 CH 2 NMe 2− 2)2(2)(16),其中强配位的NMe 2基团降低了烷基化速率(7),或者根本没有反应性(16)。当t -BuDAB与Zn [(CH 2)仅单独的2 COOEt] 2(10)形成3-吡咯烷酮(10c),而与10和ClZn(CH 2)2