Thermische Umwandlung von Penta-2, 4-dienyl-phenyläthern in 4-(Penta-2, 4-dienyl)-phenole; [5s, 5s]-sigmatropische Umlagerungen
作者:Gy. Fráter、H. Schmid
DOI:10.1002/hlca.19700530208
日期:——
trans-Penta-2, 4-dienyl phenyl ether (trans-1), on heating at 186° in a five-fold excess of N, N-diethylaniline, gave via a [3s, 3s] rearrangement 23% of 2-(1-vinyl-allyl)-phenol (2) and via a [5s, 5s] rearrangement 37% of trans-4-(penta-2, 4-dienyl)-phenol (trans-3). The dimeric residue was formed from trans-1 by diene synthesis. By working at high dilution, the formation of dimeric products was kept
反式-五2,4二烯基苯基醚(反式- 1),对在五倍过量的N,N-二乙基苯胺在186°加热,经由给[3S,3S]重排的2- 23%( 1-乙烯基-烯丙基) -苯酚(2)和经由[5S,5S]重排的37%的反式-4-(五2,4二烯基) -苯酚(反式- 3)。二聚体残余物从形成反式- 1由二烯合成。通过高稀释度工作,二聚产物的形成保持在最低限度。迁移戊二烯基残基的重排期间反转的反式- 1到反式- 3通过标记的醚的甲基的重排证明反,反- 4到p -dienyl -苯酚8(93%)(伴有只有7%的9)。反式- 5给p苯酚9定量。