Efficient Difluoromethylation of Alcohols Using TMSCF<sub>2</sub>Br as a Unique and Practical Difluorocarbene Reagent under Mild Conditions
作者:Qiqiang Xie、Chuanfa Ni、Rongyi Zhang、Lingchun Li、Jian Rong、Jinbo Hu
DOI:10.1002/anie.201611823
日期:2017.3.13
difluoromethylation of alcohols using commercially available TMSCF2Br (TMS=trimethylsilyl) as a unique and practical difluorocarbene source is developed. This method allows primary, secondary, and even tertiary alkyl difluoromethyl ethers to be synthesized under weakly basic or acidic conditions. The reaction mainly proceeds through the direct interaction between a neutral alcohol and difluorocarbene
Deoxygenative <i>gem</i>-difluoroolefination of carbonyl compounds with (chlorodifluoromethyl)trimethylsilane and triphenylphosphine
作者:Fei Wang、Lingchun Li、Chuanfa Ni、Jinbo Hu
DOI:10.3762/bjoc.10.32
日期:——
phosphonium ylide represents one of the most straightforward methods. RESULTS: The combination of (chlorodifluoromethyl)trimethylsilane (TMSCF2Cl) and triphenylphosphine (PPh3) can be used for the synthesis of gem-difluoroolefins from carbonyl compounds. Comparative experiments demonstrate that TMSCF2Cl is superior to (bromodifluoromethyl)trimethylsilane (TMSCF2Br) and (trifluoromethyl)trimethylsilane
Nickel-Catalyzed Decarbonylative Synthesis of Fluoroalkyl Thioethers
作者:Conor E. Brigham、Christian A. Malapit、Naish Lalloo、Melanie S. Sanford
DOI:10.1021/acscatal.0c02950
日期:2020.8.7
This report describes the development of a nickel-catalyzed decarbonylative reaction for the synthesis of fluoroalkyl thioethers (RFSR) from the corresponding thioesters. Readily available, inexpensive, and stable fluoroalkyl carboxylic acids (RFCO2H) serve as the fluoroalkyl (RF) source in this transformation. Stoichiometric organometallic studies reveal that RF–S bond-forming reductive elimination
本报告描述了镍催化脱羰反应的发展,用于从相应的硫酯合成氟烷基硫醚 (R F SR)。容易获得、便宜且稳定的氟代烷基羧酸 (R F CO 2 H) 作为该转化中的氟代烷基 (R F ) 源。化学计量有机金属研究表明,形成R F -S 键的还原消除是催化循环中的一个具有挑战性的步骤。这导致二苯基膦二茂铁被鉴定为该转化的最佳配体。最终,该方法应用于构建多种氟代烷基硫醚 (R F SR),其中 R = 芳基和烷基。
Iron-Catalyzed, Site-Selective Difluoromethylthiolation (−SCF<sub>2</sub>H) and Difluoromethylselenation (−SeCF<sub>2</sub>H) of Unactivated C(sp<sup>3</sup>)–H Bonds in <i>N</i>-Fluoroamides
作者:Hongwei Zhang、Fei Yu、Chuang Li、Peiyuan Tian、Yulu Zhou、Zhong-Yan Cao
DOI:10.1021/acs.orglett.1c01443
日期:2021.6.18
The iron-catalyzed δ-C(sp3)–H bond difluoromethylthiolation and difluoromethylselenation of aliphatic amides with high site selectivity are reported. Essential to the success is the employment of an amide radical formed in situ to activate the inert C(sp3)–H bond and the utilization of the easily handled PhSO2SCF2H and PhSO2SeCF2H as coupling reagents under mild conditions. This scalable protocol exhibits
报道了铁催化的 δ-C(sp 3 )-H 键二氟甲硫基化和脂肪族酰胺的二氟甲基硒化,具有高位点选择性。成功的关键是使用原位形成的酰胺自由基来激活惰性 C(sp 3 )-H 键,并在温和条件下使用易于处理的 PhSO 2 SCF 2 H 和 PhSO 2 SeCF 2 H 作为偶联剂. 这种可扩展的协议展示了具有多功能功能组的广泛基板范围。机理研究表明,反应通过-SCF 2 H 和-SeCF 2 H 自由基转移进行。