55805-10-2Relevant articles and documents
Synthesis of L-Au(I)-CF2H Complexes and Their Application as Transmetalation Shuttles to the Difluoromethylation of Aryl Iodides
García-Domínguez, Patricia
supporting information, p. 2923 - 2928 (2021/09/07)
We describe herein two alternative protocols to efficiently prepare difluoromethylgold(I) complexes bearing ancillary ligands with different electronic and steric properties. LAu-OX (X = H andt-Bu) species, formed in the presence of base, have been identified as intermediate complexes involved in these transformations. The application of these compounds as “CF2H transmetalation shuttles” from gold to palladium has been demonstrated in a Pd-catalyzed difluoromethylation reaction of aryl iodides, in which the Au-to-Pd transfer of “CF2H” is feasible under stoichiometric conditions. These findings will pave the way for catalytic manifolds in gold chemistry.
METHOD AND REAGENT FOR DEOXYFLUORINATION
-
Paragraph 0148-0150; 0152, (2021/05/29)
A safe, simple, and selective method and reagent for deoxyfluorination is disclosed. With the method and reagent disclosed herein, organic compounds such as carboxylic acids, carboxylates, carboxylic acid anhydrides, aldehydes, and alcohols can be fluorinated by using the most common nucleophilic fluorinating reagents and electron deficient fluoroarenes as mediators under mild conditions, giving corresponding fluoroorganic compounds in excellent yield with a wide range of functional group compatibility and easy product purification. For example, directly utilizing KF for deoxyfluorination of carboxylic acids provides the most economical and the safest pathway to access acyl fluorides, key intermediates for syntheses of peptide, amide, ester, and dry fluoride salts.
Decarbonylative Fluoroalkylation at Palladium(II): From Fundamental Organometallic Studies to Catalysis
Lalloo, Naish,Malapit, Christian A.,Taimoory, S. Maryamdokht,Brigham, Conor E.,Sanford, Melanie S.
supporting information, p. 18617 - 18625 (2021/11/16)
This Article describes the development of a decarbonylative Pd-catalyzed aryl-fluoroalkyl bond-forming reaction that couples fluoroalkylcarboxylic acid-derived electrophiles [RFC(O)X] with aryl organometallics (Ar-M′). This reaction was optimized by interrogating the individual steps of the catalytic cycle (oxidative addition, carbonyl de-insertion, transmetalation, and reductive elimination) to identify a compatible pair of coupling partners and an appropriate Pd catalyst. These stoichiometric organometallic studies revealed several critical elements for reaction design. First, uncatalyzed background reactions between RFC(O)X and Ar-M′ can be avoided by using M′ = boronate ester. Second, carbonyl de-insertion and Ar-RF reductive elimination are the two slowest steps of the catalytic cycle when RF = CF3. Both steps are dramatically accelerated upon changing to RF = CHF2. Computational studies reveal that a favorable F2C-H - -X interaction contributes to accelerating carbonyl de-insertion in this system. Finally, transmetalation is slow with X = difluoroacetate but fast with X = F. Ultimately, these studies enabled the development of an (SPhos)Pd-catalyzed decarbonylative difluoromethylation of aryl neopentylglycol boronate esters with difluoroacetyl fluoride.
