Me<sub>2</sub>Zn-Mediated Addition of Acetylenes to Aldehydes and Ketones
作者:Pier Giorgio Cozzi、Jens Rudolph、Carsten Bolm、Per-Ola Norrby、Claudia Tomasini
DOI:10.1021/jo050115r
日期:2005.7.1
Contrary to expectations, commercially available 2 M Me2Zn in toluene is able to promote the addition of phenylacetylene to aldehydes and ketones. This reactivity is determined by a new, unprecedented mechanism, which involves activation of the zinc reagent via coordination with carbonyl substrates that behave “ligand like”. Broad scope, high tolerance to functional groups, and a simple procedure make
与预期相反,在甲苯中可商购的2 M Me 2 Zn能够促进将苯乙炔添加到醛和酮中。这种反应性是由一种新的,前所未有的机制决定的,该机制涉及通过与表现为“配体样”的羰基底物的配位来激活锌试剂。宽泛的范围,对官能团的高度耐受性以及简单的操作步骤使这种新方法对于合成化学家而言非常有趣。
Enantioselective alkynylations of aromatic and aliphatic aldehydes catalyzed by terpene derived chiral amino alcohols
作者:Cian Christopher Watts、Praveen Thoniyot、Lacie C. Hirayama、Talia Romano、Bakthan Singaram
DOI:10.1016/j.tetasy.2005.03.036
日期:2005.5
Enantioselective alkynyl zinc additions to aromatic and aliphatic aldehydes have been studied using terpene derived chiral amino alcohol ligands. The limonene derived amino alcohol (1R,2R,5S)-2-methyl-5-(1-methylethenyl)-2-(1-pyrrolidinyl)cyclohexanol gave the most promising results. Chiral propargylic alcohols were obtained in good yields and moderate enantioselectivities (up to 60%).
Direct conversion of secondary propargyl alcohols into 1,3-di-arylpropanone <i>via</i> DBU promoted redox isomerization and palladium assisted chemoselective hydrogenation in a single pot operation
作者:Rimpa De、S. Antony Savarimuthu、Shubhadeep Chandra、Mrinal K. Bera
DOI:10.1039/d1nj02972j
日期:——
Palladium(II)acetate is found to be an efficient catalyst for the single-step conversion of secondary propargyl alcohols to 1,3-diarylpropanone derivatives under mild basic conditions. The reaction is believed to proceed via redox isomerisation of secondary propargyl alcohols followed by chemoselective reduction of an enone double bond with formic acid as an adequate hydrogen donor. A large number
发现乙酸钯 ( II ) 是一种有效的催化剂,可在温和的碱性条件下将仲炔醇一步转化为 1,3-二芳基丙酮衍生物。据信,该反应通过仲炔丙醇的氧化还原异构化,然后用甲酸作为适当的氢供体对烯酮双键进行化学选择性还原而进行。大量的 1,3-二芳基丙酮衍生物可以很容易地从毫克级到几克级制备。
1,1′-Binaphthyl ligands with bulky 3,3′-tertiaryalkyl substituents for the asymmetric alkyne addition to aromatic aldehydes
作者:Qin Wang、Shan-Yong Chen、Xiao-Qi Yu、Lin Pu
DOI:10.1016/j.tet.2007.03.080
日期:2007.5
The BINOL ligand (R)-2 that contains bulky 3,3'-tertiaryalkyl groups shows improved catalytic properties than the previously reported 3,3'-substituted BINOL ligands in the asymmetric alkyne addition to aromatic aldehydes. It can catalyze the phenylacetylene addition to aromatic aldehydes with high enantioselectivity (86 - 94% ee) and good yields without using Ti(O(i)Pr)(4) and a Lewis base additive
Ligand-Promoted, Copper Nanoparticles Catalyzed Oxidation of Propargylic Alcohols with TBHP or Air as Oxidant
作者:Xiaoquan Yao、Chengyan Han、Min Yu、Weijiang Sun
DOI:10.1055/s-0030-1261227
日期:2011.10
A highly efficient oxidation of propargylicalcohols to ynones was catalyzed by copper nanoparticles (Cu Nps) with TBHP as an oxidant at room temperature. With bipyridine as the ligand, the reaction was accelerated significantly and led in good to excellent yields to a variety of propargylicalcohols. Furthermore, with Cu Nps as the catalyst, molecular oxygen in air could be utilized as oxidant effectively