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。
The trimethylgallium reagent was found to promote the addition of phenylacetylene to various aromatic and aliphatic aldehydes. This reaction was efficiently carried out in anhydrous CH2Cl2 at room temperature under mild conditions and the corresponding propargylic alcohols were obtained in good to excellent yields up to 98%.
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
process that involves the Meyer–Schusterrearrangement of alkynols followed by the Diels–Alder cycloaddition of the resulting enones. These reactions were performed under mild conditions in the presence of 5 mol-% of the catalyst to afford the cycloadducts in good yields with almost 100 % endo stereoselectivity. In-depth computational studies of the cycloaddition mechanism provided the preferred geometry
Flexible Construction of Functionalized‐Pyrroles under Palladium or Copper Catalysis in the Presence of BF
<sub>3</sub>
⋅ Et
<sub>2</sub>
O
作者:Yin Liu、Teng Liu、Biwei Yan、Kun Wei、Wusheng Guo
DOI:10.1002/adsc.202101292
日期:2022.3
friendly operations with the generation of only water as byproduct. The generality of this protocol is demonstrated by the successful preparation of a range of di-, tri-, tetra- and pentasubstituted pyrroles. This methodology is amenable for the synthesis and derivatization of bioactive compounds.
我们开发了一种灵活的方法,能够在 BF 3 ⋅ Et 2 O 的存在下,在钯或铜催化下获得高度官能化的吡咯。这种催化方法利用市售胺作为反应伙伴,具有广泛的范围、可扩展和友好的操作仅产生水作为副产品。该协议的普遍性通过一系列二、三、四和五取代吡咯的成功制备得到证明。该方法适用于生物活性化合物的合成和衍生化。