Metal-Free and User-Friendly Regioselective Hydroxyfluorination of Olefins
作者:Daniel M. Sedgwick、Inés López、Raquel Román、Nanako Kobayashi、Otome E. Okoromoba、Bo Xu、Gerald B. Hammond、Pablo Barrio、Santos Fustero
DOI:10.1021/acs.orglett.8b00681
日期:2018.4.20
inexpensive reagents has been developed. This new approach displays a broader scope than previously reported methodologies and has been applied to the late-stage fluorination of a complex molecule, giving rise to a fluorosteroid derivative. The stereochemistry of the process has also been studied in some detail.
Catalytic enantioselective α‐fluorination reactions of carbonyl compounds are among the most powerful and efficient synthetic methods for constructing optically active α‐fluorinated carbonyl compounds. Nevertheless, α‐fluorination of α‐nonbranched carboxylic acid derivatives is still a big challenge because of relatively high pKa values of their α‐hydrogen atoms and difficulty of subsequent synthetic
羰基化合物的催化对映选择性α-氟化反应是构建光学活性α-氟化羰基化合物的最有效,最有效的合成方法之一。然而,由于α-非支链羧酸衍生物的α-氢原子的p K a值相对较高,并且随后不进行差向异构化就很难进行合成转化,因此α-非支链羧酸衍生物的α-氟化仍然是一个很大的挑战。本文显示了3-(2-萘基)-1-丙氨酸衍生的酰胺的手性铜(II)络合物是N-(α-芳基乙酰基)和N的对映体和定点α-氟化的高效催化剂-(α-烷基乙酰基)3,5-二甲基吡唑。转化的底物范围非常广泛(25个实例,其中包括季铵化α-氟化α-氨基酸衍生物)。α-氟化产物几乎没有差向异构化地转化为相应的酯,仲酰胺,叔酰胺,酮和醇。
Enantioselective alpha-fluorination of aldehydes using chiral organic catalysts
申请人:MacMillan W.C. David
公开号:US20060189830A1
公开(公告)日:2006-08-24
Nonmetallic, chiral organic catalysts are used to catalyze enantioselective fluorination of enolizable aldehydes. Reaction systems composed of an enolizable aldehyde, an electrophilic fluorination reagent, and a nonmetallic chiral catalyst in the form of an imidazolidinone salt are also provided.
Regioselective Synthesis ofFluorohydrines via S<sub>N</sub>2-Type Ring-Opening of Epoxideswith TBABF-KHF<sub>2</sub>
作者:Shoji Hara、Yuriko Akiyama、Tsuyoshi Fukuhara
DOI:10.1055/s-2003-40865
日期:——
We found that the ring-opening fluorination of terminal epoxides using TBABF-KHF2 proceeds with high selectivity through the SN2 mechanism. As TBABF-KHF2 is easily obtainable, is stable, and can be used in glassware, it can be a useful reagent for 1-fluoro-2-alkanol synthesis from the terminal epoxides.
[2.2]Paracyclophane-Based Isothiourea-Catalyzed Highly Enantioselective α-Fluorination of Carboxylic Acids
作者:Shiru Yuan、Chen Liao、Wen-Hua Zheng
DOI:10.1021/acs.orglett.1c01046
日期:2021.6.4
catalysts have been prepared over a few simple steps in high yields. In the presence of these catalysts, highly efficient catalytic enantioselective fluorination of carboxylic acids has been accomplished, providing a broad range of optically active α-fluoroesters in high yield and excellent enantioselectivity.