摘要 已发现胆碱氢氧化物(ChOH)是一种绿色高效的碱性离子液体催化剂,可通过以下反应合成高度官能化的吡啶并[2',3':3,4]吡唑并[1,5- a ]嘧啶衍生物。在纯条件下用1 H-吡唑并[3,4- b ]吡啶-3-胺形成的一系列α,β-不饱和酮。一系列α,β高效地将具有不同取代官能团的不饱和酮转化为相应的产物,分离产率高至优异,反应可轻松放大至几克。本发明对环境无害且可重复使用的ChOH催化剂具有几个优点,例如反应时间更短,官能团耐受性范围广以及通过简单的实验和后处理程序即可获得高产率的产物。 图形概要 该方法的主要特点是绿色反应,操作简便,可重复使用,易操作性强,ChOH效率高。
Ligand-free CuI-catalyzed bis(pinacolato)diboron (B2(pin)2) conjugate addition and reduction onto α,β-unsaturated carbonyl compounds in moderate to excellent yields has been demonstrated.
Silicon as a directing group in the phosphine-catalyzed [2 + 3]-cycloaddition of aryl allenones with electron-deficient olefins
作者:Magesh Sampath、Teck-Peng Loh
DOI:10.1039/b819959k
日期:——
This Communication describes a highly efficient phosphine-catalyzed [2+3]-cycloaddition reaction using alpha-trimethylsilyl-substituted aryl allenones and electron deficient olefins; both good yields and good asymmetric induction were obtained.
CBr<sub>4</sub> as a Halogen Bond Donor Catalyst for the Selective Activation of Benzaldehydes to Synthesize α,β-Unsaturated Ketones
作者:Imran Kazi、Somraj Guha、Govindasamy Sekar
DOI:10.1021/acs.orglett.7b00348
日期:2017.3.3
CBr4 has been employed as a halogen bond donor catalyst for the selective activation of aldehyde, to achieve an efficient solvent- and metal-free C═C bond forming reaction in the presence of strong acid sensitive groups such as methoxy, cyanide, ester, and ketal for the synthesis of α,β-unsaturated ketones. This unique capability of CBr4 to act as a halogen bond donor has been explored and established