ABSTRACT A transition metal-free, direct one-potdominoallylation reaction of 2-pyridinyl Grignard reagents with polysubstituted allyl chlorides for the regioselective synthesis of pyridinyl-substituted 1,5-diene derivatives has been disclosed. The reaction presumably proceeded through the coupling of polysubstituted allyl chloride to 2-PyMgX, which was in situ generated from 2-bromopyridine with
Preference for β-H elimination in the termination of the Ni-promoted carbonylative cycloaddition of 2-haloethylidene-cycloalkanes and alkynes
作者:Fabiola Vilaseca、Lluı́s Pagès、Juan Manuel Villar、Amadeu Llebaria、Antonio Delgado、Josep Maria Moretó
DOI:10.1016/s0022-328x(97)00390-2
日期:1998.1
mutual conformation of the two rings in the intermediates favouring either elimination through enol formation or synβ-elimination. In this last case, the terminating step can proceed in two different modes, namely, intraannularly or interannularly. While for the acetylenic ester, the product from interannular elimination is exclusive or predominant regardless of the ring size of the starting halide,
Direct Conversion of Aldehydes and Ketones to Allylic Halides by a NbX5-[3,3] Rearrangement
作者:Fraser Fleming、P. Ravikumar、Lihua Yao
DOI:10.1055/s-0028-1088222
日期:2009.4
bromide and NbCl(5), or NbBr(5), to a series of aldehydes and ketones directly provides homologated, allylic halides. Transposition of the intermediate vinyl alkoxide is envisaged through a metalla-halo-[3,3] rearrangement with concomitant delivery of the halogen to the terminal carbon. The [3,3] rearrangement is equally effective for the conversion of a propargyllic alcohol to the corresponding allenyl
A Novel One-Pot Conversion of Allyl Alcohols into Primary Allyl Halides Mediated by Acetyl Halide
作者:Nurhan Kishali、M. Fatih Polat、Ramazan Altundas、Yunus Kara
DOI:10.1002/hlca.200890014
日期:2008.1
primary allyl chlorides and bromides 9–16 from the secondary or tertiary allylalcohols 3–8 and acyl halide was developed (Scheme 2, Table 1). Non-commercially available secondary and tertiary allylalcohols were synthesized from the related ketones and aldehydes via the addition of vinylmagnesium chloride. Mechanistic studies indicate that the alcohols were first acetylated by the acetyl halide and then
Pd(0)-catalyzed cross-coupling of allyl halides with α-diazocarbonyl compounds or N-mesylhydrazones: synthesis of 1,3-diene compounds
作者:Kang Wang、Shufeng Chen、Hang Zhang、Shuai Xu、Fei Ye、Yan Zhang、Jianbo Wang
DOI:10.1039/c6ob00454g
日期:——
With palladiumcatalysis, allyl bromides or chlorides react with α-diazocarbonyl compounds or N-mesylhydrazones to afford 1,3-diene derivatives. The reaction represents a novel and efficient method for the synthesis of 1,3-butadiene derivatives. Mechanistically, the reaction is proposed to follow a pathway involving the formation of a π-allylic palladium carbene complex and subsequent migratory insertion