Synthesis of Arylallenes by Palladium-Catalyzed Retro-Propargylation of Homopropargyl Alcohols
摘要:
Treatment of tertiary homopropargyl alcohol with aryl halide under palladium catalysis provided arylallenes regioselectively. The reaction includes retropropargylation, which proceeds in a concerted fashion via a cyclic transition state and transfers the stereochemistry of homopropargyl alcohols through C-C bond cleavage. The present method enables the use of homopropargyl alcohols as allenylmetal equivalents.
Iron-Catalyzed Direct Synthesis of Densely Substituted Benzofurans and Naphthopyrans from Phenolic Compounds and Propargylic Alcohols
作者:Feng-Quan Yuan、Fu-She Han
DOI:10.1002/adsc.201200804
日期:2013.2.1
propargylic alcohols in the presence of 5 mol% of iron(III) chloride hexahydrate (FeCl3⋅6 H2O) catalyst. On the other hand, pyran derivatives were obtained exclusively when tertiary propargylic alcohols were employed. Mechanistic studies revealed that presumably due to the discriminated steric effect of secondary and tertiary propargylic alcohols, the Fe-catalyzed Friedel–Crafts (F–C) reaction of phenols
Rh‐Catalyzed Reaction of Propargylic Alcohols with Aryl Boronic Acids–Switch from β‐OH Elimination to Protodemetalation
作者:Weiyi Wang、Hui Qian、Shengming Ma
DOI:10.1002/cjoc.202000044
日期:2020.4
It is known that Rh‐catalyzed reaction of propargylic alcohols with aryl metallic reagents undergoes SN2’‐type reaction affording allenes via a sequential arylmetalation and β‐OH elimination process. Here we report a Rh/Ag‐cocatalyzed reaction of propargylic alcohols with organoboronic acids affording stereo‐defined (E)‐3‐arylallylic alcohols via arylmetalation and protodemetalation with a high regio‐
众所周知,炔丙醇与芳基金属试剂的Rh催化反应会经历S N 2'型反应,这是通过顺序的芳基金属化和β-OH消除过程提供的。在此我们报道了炔丙醇与有机硼酸的Rh / Ag催化反应,在非常温和的条件下,通过芳基金属化和原金属脱金属以高区域和立体选择性提供了立体定义的(E)-3-芳基烯丙醇。该反应显示出良好的底物范围以及与合成有用的官能团的相容性,而对于旋光的炔丙醇没有外消旋作用。这种反应还可以扩展为具有显着的区域选择性和排他性E-立体选择性的均丙醇。
Duchon d'Engenieres,M., Bulletin de la Societe Chimique de France, 1968, p. 201 - 204
作者:Duchon d'Engenieres,M.
DOI:——
日期:——
PEARSON, N. R.;HAHN, G.;ZWEIFEL, G., J. ORG. CHEM., 1982, 47, N 17, 3364-3366
作者:PEARSON, N. R.、HAHN, G.、ZWEIFEL, G.
DOI:——
日期:——
Hg(OTf)2-Catalyzed Instantaneous Hydration of β- and δ-Hydroxy Internal Alkynes with Complete Regioselectivity
The hydration of β- and δ-hydroxy internal alkynes catalyzed by Hg(OTf)2 took place instantaneously to give ketones with complete regioselectivity under mild conditions, whereas the hydration of internal alkyne without hydroxy moiety was very slow and gave a mixture of ketones. If the hydroxy group is located more than five carbons from the triple bond it has no significant effect upon the hydration reaction.