1-三甲苯基异戊烯(1),1-三甲苯基-3-甲基丙二烯(2)和1-三甲苯基-3,3-二甲基丙二烯(3)在癸烷中通过[1.5 s ]σ-H-在150-190°下热重排移位得到邻喹啉甲烷4,其环化生成1,2-二氢萘5和6和/或经历[1,7 a ]σH移位得到1-甲磺酰基-(Z)-buta-1, 3-二烯(Z)-7和(Z)-8(方案1,3,4和5)的数量几乎是定量的。这些异构化的活化参数在表1中给出。1-Mesityl-1-甲基丙二烯(9)在190°下异构化,以4,50 %的收率得到4,5,7-三甲基-1,2-二氢萘(17)。方案6)。
Cu(I)-NHC-Catalyzed Silylation of Allenes: Diastereoselective Three-Component Coupling with Aldehydes
作者:James Rae、Ya Chu Hu、David J. Procter
DOI:10.1002/chem.201404330
日期:2014.10.6
Copper‐catalyzed silylation of aryl allenes using a silylborane reagent affords vinyl silane building blocks with high efficiency. The use of a seven‐membered NHC ligand proved crucial for high regioselectivity. The catalytically generated allylcoppper intermediates were intercepted by aldehydes in a diastereoselective three‐component coupling to furnish homoallylic alcohols.
rhodium‐catalyzed intermolecular [3+2] cycloaddition reaction of vinyl aziridines and allenes for the synthesis of enantioenriched functionalized pyrrolidines was realized. [3+2] cycloaddition with the proximal C=C bond of N‐allenamides gave 3‐methylene‐pyrrolidines in high regio‐ and diastereoselectivity, whereas, 2‐methylene‐pyrrolidines were obtained as the major products by the cycloadditions of vinyl aziridines
The acid catalysed dienol-benzene rearrangement of methyl substituted o- and p-propargylcyclohexadienols (18–22, 34 and 35) was investigated. In the first step water is eliminated to yield the corresponding methyl propargyl benzonium ions (cf. scheme 6, a), which undergo [1s, 2s] sigmatropic rearrangements to give propargylbenzenes (28, 29, 30, 38) and [3s, 4s] sigmatropic rearrangements to give allenylbenzenes
的甲基substituiertem的酸催化二烯醇-苯重排ø -和p -propargylcyclohexadienols(18-22,34和35,其考察)。在第一步骤中的水被消除,得到相应的甲基炔丙基benzonium离子(参见方案6,一个),其经历[1级小号,2个小号]σ迁移重排,得到propargylbenzenes(28,29,30,38)和[3小号,4小号]σ迁移重排,得到allenylbenzenes(24-27,40)(参见方案2,3,5,6)。[3s,3 s ]σ重排仅在很小的范围内发生。在2-炔丙基-2,4,6-三甲基环己-3,5-二烯-1-醇(18)的重排中,观察到[1 s,2 s ]σ甲基位移(4%)。
Reaktionen mit Phosphinalkylenen; VL<sup>1</sup>. Synthese von aryl-substituierten Allenen und Styrylallen aus Aldehyden und Phosphonium-yliden
作者:Hans Jürgen Bestmann、Herbert Frey
DOI:10.1055/s-1984-30790
日期:——
BESTMANN, H. J.;FREY, H., SYNTHESIS, BRD, 1984, N 3, 243