@article{HuangHuShietal.2022,
  author    = {Huang, Mingming and Hu, Jiefeng and Shi, Shasha and Friedrich, Alexandra and Krebs, Johannes and Westcott, Stephen A. and Radius, Udo and Marder, Todd B.},
  title     = {Selective, Transition Metal-free 1,2-Diboration of Alkyl Halides, Tosylates, and Alcohols},
  series = {Chemistry-A European Journal},
  volume    = {28},
  journal   = {Chemistry-A European Journal},
  number    = {24},
  doi       = {10.1002/chem.202200480},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-318262},
  year      = {2022},
  abstract  = {Defunctionalization of readily available feedstocks to provide alkenes for the synthesis of multifunctional molecules represents an extremely useful process in organic synthesis. Herein, we describe a transition metal-free, simple and efficient strategy to access alkyl 1,2-bis(boronate esters) via regio- and diastereoselective diboration of secondary and tertiary alkyl halides (Br, Cl, I), tosylates, and alcohols. Control experiments demonstrated that the key to this high reactivity and selectivity is the addition of a combination of potassium iodide and N,N-dimethylacetamide (DMA). The practicality and industrial potential of this transformation are demonstrated by its operational simplicity, wide functional group tolerance, and the late-stage modification of complex molecules. From a drug discovery perspective, this synthetic method offers control of the position of diversification and diastereoselectivity in complex ring scaffolds, which would be especially useful in a lead optimization program.},
  language  = {en}
}
@article{LiuBudimanTianetal.2020,
  author    = {Liu, Zhiqiang and Budiman, Yudha P. and Tian, Ya-Ming and Friedrich, Alexandra and Huang, Mingming and Westcott, Stephen A. and Radius, Udo and Marder, Todd B.},
  title     = {Copper-Catalyzed Oxidative Cross-Coupling of Electron-Deficient Polyfluorophenylboronate Esters with Terminal Alkynes},
  series = {Chemistry - A European Journal},
  volume    = {26},
  journal   = {Chemistry - A European Journal},
  number    = {71},
  doi       = {10.1002/chem.202002888},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-224362},
  pages     = {17267 -- 17274},
  year      = {2020},
  abstract  = {We report herein a mild procedure for the copper-catalyzed oxidative cross-coupling of electron-deficient polyfluorophenylboronate esters with terminal alkynes. This method displays good functional group tolerance and broad substrate scope, generating cross-coupled alkynyl(fluoro)arene products in moderate to excellent yields. Thus, it represents a simple alternative to the conventional Sonogashira reaction.},
  language  = {en}
}
@article{JosSzwetkowskiSlebodnicketal.2022,
  author    = {Jos, Swetha and Szwetkowski, Connor and Slebodnick, Carla and Ricker, Robert and Chan, Ka Lok and Chan, Wing Chun and Radius, Udo and Lin, Zhenyang and Marder, Todd B. and Santos, Webster L.},
  title     = {Transition Metal-Free Regio- and Stereo-Selective trans Hydroboration of 1,3-Diynes: A Phosphine-Catalyzed Access to (E)-1-Boryl-1,3-Enynes},
  series = {Chemistry - A European Journal},
  volume    = {28},
  journal   = {Chemistry - A European Journal},
  number    = {63},
  doi       = {10.1002/chem.202202349},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-293784},
  year      = {2022},
  abstract  = {We report a transition metal-free, regio- and stereo-selective, phosphine-catalyzed method for the trans hydroboration of 1,3-diynes with pinacolborane that affords (E)-1-boryl-1,3-enynes. The reaction proceeds with excellent selectivity for boron addition to the external carbon of the 1,3-diyne framework as unambiguously established by NMR and X-ray crystallographic studies. The reaction displays a broad substrate scope including unsymmetrical diynes to generate products in high yield (up to 95 \%). Experimental and theoretical studies suggest that phosphine attack on the alkyne is a key process in the catalytic cycle.},
  language  = {en}
}
@article{HuangWuKrebsetal.2021,
  author    = {Huang, Mingming and Wu, Zhu and Krebs, Johannes and Friedrich, Alexandra and Luo, Xiaoling and Westcott, Stephen A. and Radius, Udo and Marder, Todd B.},
  title     = {Ni-Catalyzed Borylation of Aryl Sulfoxides},
  series = {Chemistry—A European Journal},
  volume    = {27},
  journal   = {Chemistry—A European Journal},
  number    = {31},
  doi       = {10.1002/chem.202100342},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-256778},
  pages     = {8149-8158},
  year      = {2021},
  abstract  = {A nickel/N-heterocyclic carbene (NHC) catalytic system has been developed for the borylation of aryl sulfoxides with B\(_{2}\)(neop)\(_{2}\) (neop=neopentyl glycolato). A wide range of aryl sulfoxides with different electronic and steric properties were converted into the corresponding arylboronic esters in good yields. The regioselective borylation of unsymmetric diaryl sulfoxides was also feasible leading to borylation of the sterically less encumbered aryl substituent. Competition experiments demonstrated that an electron-deficient aryl moiety reacts preferentially. The origin of the selectivity in the Ni-catalyzed borylation of electronically biased unsymmetrical diaryl sulfoxide lies in the oxidative addition step of the catalytic cycle, as oxidative addition of methoxyphenyl 4-(trifluoromethyl)phenyl sulfoxide to the Ni(0) complex occurs selectively to give the structurally characterized complex trans-[Ni(ICy)\(_{2}\)(4-CF\(_{3}\)-C\(_{6}\)H\(_{4}\)){(SO)-4-MeO-C\(_{6}\)H\(_{4}\)}] 4. For complex 5, the isomer trans-[Ni(ICy)\(_{2}\)(C\(_{6}\)H\(_{5}\))(OSC\(_{6}\)H\(_{5}\))] 5-I was structurally characterized in which the phenyl sulfinyl ligand is bound via the oxygen atom to nickel. In solution, the complex trans-[Ni(ICy)\(_{2}\)(C\(_{6}\)H\(_{5}\))(OSC\(_{6}\)H\(_{5}\))] 5-I is in equilibrium with the S-bonded isomer trans-[Ni(ICy)\(_{2}\)(C\(_{6}\)H\(_{5}\))(SOC\(_{6}\)H\(_{5}\))] 5, as shown by NMR spectroscopy. DFT calculations reveal that these isomers are separated by a mere 0.3 kJ/mol (M06/def2-TZVP-level of theory) and connected via a transition state trans-[Ni(ICy)\(_{2}\)(C\(_{6}\)H\(_{5}\))(η\(^{2}\)-{SO}-C\(_{6}\)H\(_{5}\))], which lies only 10.8 kcal/mol above 5.},
  language  = {en}
}
@article{LiuKoleBudimanetal.2021,
  author    = {Liu, Zhiqiang and Kole, Goutam Kumar and Budiman, Yudha P. and Tian, Ya-Ming and Friedrich, Alexandra and Luo, Xiaoling and Westcott, Stephen A. and Radius, Udo and Marder, Todd B.},
  title     = {Transition metal catalyst-free, base-promoted 1,2-additions of polyfluorophenylboronates to aldehydes and ketones},
  series = {Angewandte Chemie International Edition},
  volume    = {60},
  journal   = {Angewandte Chemie International Edition},
  number    = {30},
  doi       = {10.1002/anie.202103686},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-256487},
  pages     = {16529-16538},
  year      = {2021},
  abstract  = {A novel protocol for the transition metal-free 1,2-addition of polyfluoroaryl boronate esters to aldehydes and ketones is reported, which provides secondary alcohols, tertiary alcohols, and ketones. Control experiments and DFT calculations indicate that both the ortho-F substituents on the polyfluorophenyl boronates and the counterion K\(^+\) in the carbonate base are critical. The distinguishing features of this procedure include the employment of commercially available starting materials and the broad scope of the reaction with a wide variety of carbonyl compounds giving moderate to excellent yields. Intriguing structural features involving O-H⋅⋅⋅O and O-H⋅⋅⋅N hydrogen bonding, as well as arene-perfluoroarene interactions, in this series of racemic polyfluoroaryl carbinols have also been addressed.},
  language  = {en}
}
@article{BudimanWestcottRadiusetal.2021,
  author    = {Budiman, Yudha P. and Westcott, Stephen A. and Radius, Udo and Marder, Todd B.},
  title     = {Fluorinated Aryl Boronates as Building Blocks in Organic Synthesis},
  series = {Advanced Synthesis \& Catalysis},
  volume    = {363},
  journal   = {Advanced Synthesis \& Catalysis},
  number    = {9},
  doi       = {10.1002/adsc.202001291},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225908},
  pages     = {2224 -- 2255},
  year      = {2021},
  abstract  = {Organoboron compounds are well known building blocks for many organic reactions. However, under basic conditions, polyfluorinated aryl boronic acid derivatives suffer from instability issues that are accelerated in compounds containing an ortho-fluorine group, which result in the formation of the corresponding protodeboronation products. Therefore, a considerable amount of research has focused on novel methodologies to synthesize these valuable compounds while avoiding the protodeboronation issue. This review summarizes the latest developments in the synthesis of fluorinated aryl boronic acid derivatives and their applications in cross-coupling reactions and other transformations. image},
  language  = {en}
}
@article{BudimanFriedrichRadiusetal.2019,
  author    = {Budiman, Yudha P. and Friedrich, Alexandra and Radius, Udo and Marder, Todd B.},
  title     = {Copper-catalysed Suzuki-Miyaura cross-coupling of highly fluorinated aryl boronate esters with aryl iodides and bromides and fluoroarene-arene π-stacking interactions in the products},
  series = {ChemCatChem},
  volume    = {11},
  journal   = {ChemCatChem},
  number    = {21},
  doi       = {10.1002/cctc.201901220},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-204839},
  pages     = {5387-5396},
  year      = {2019},
  abstract  = {A combination of copper iodide and phenanthroline as the ligand is an efficient catalyst for Suzuki-Miyaura cross-coupling of highly fluorinated boronate esters (aryl-Bpin) with aryl iodides and bromides to generate fluorinated biaryls in good to excellent yields. This method represents a nice alternative to traditional cross-coupling methods which require palladium catalysts and stoichiometric amounts of silver oxide. We note that π⋅⋅⋅π stacking interactions dominate the molecular packing in the partly fluorinated biaryl crystals investigated herein. They are present either between the arene and perfluoroarene, or solely between arenes or perfluoroarenes, respectively.},
  language  = {en}
}
@article{BudimanLorenzenLiuetal.2021,
  author    = {Budiman, Yudha P. and Lorenzen, Sabine and Liu, Zhiqiang and Radius, Udo and Marder, Todd B.},
  title     = {Base-Free Pd-Catalyzed C-Cl Borylation of Fluorinated Aryl Chlorides},
  series = {Chemistry - A European Journal},
  volume    = {27},
  journal   = {Chemistry - A European Journal},
  number    = {11},
  doi       = {10.1002/chem.202004648},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225687},
  pages     = {3869 -- 3874},
  year      = {2021},
  abstract  = {Catalytic C-X borylation of aryl halides containing two ortho-fluorines has been found to be challenging, as most previous methods require stoichiometric amounts of base and the polyfluorinated aryl boronates suffer from protodeboronation, which is accelerated by ortho-fluorine substituents. Herein, we report that a combination of Pd(dba)2 (dba=dibenzylideneacetone) with SPhos (2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl) as a ligand is efficient to catalyze the C-Cl borylation of aryl chlorides containing two ortho-fluorine substituents. This method, conducted under base-free conditions, is compatible with the resulting di-ortho-fluorinated aryl boronate products which are sensitive to base.},
  language  = {en}
}
@article{LiuMingLuoetal.2020,
  author    = {Liu, Xiaocui and Ming, Wenbo and Luo, Xiaoling and Friedrich, Alexandra and Maier, Jan and Radius, Udo and Santos, Webster L. and Marder, Todd B.},
  title     = {Regio- and Stereoselective Synthesis of 1,1-Diborylalkenes via Br{\o}nsted Base-Catalyzed Mixed Diboration of Alkynyl Esters and Amides with BpinBdan},
  series = {European Journal of Organic Chemistry},
  volume    = {2020},
  journal   = {European Journal of Organic Chemistry},
  number    = {13},
  doi       = {10.1002/ejoc.202000128},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-214728},
  pages     = {1941 -- 1946},
  year      = {2020},
  abstract  = {The NaOtBu-catalyzed mixed 1,1-diboration of terminal alkynes using the unsymmetrical diboron reagent BpinBdan (pin = pinacolato; dan = 1,8-diaminonaphthalene) proceeds in a regio- and stereoselective fashion affording moderate to high yields of 1,1-diborylalkenes bearing orthogonal boron protecting groups. It is applicable to gram-scale synthesis without loss of yield or selectivity. The mixed 1,1-diborylalkene products can be utilized in Suzuki-Miyaura cross-coupling reactions which take place selectivly at the C-B site. DFT calculations suggest the NaOtBu-catalyzed mixed 1,1-diboration of alkynes occurs through deprotonation of the terminal alkyne, stepwise addition of BpinBdan to the terminal carbon followed by protonation with tBuOH. Experimentally observed selective formation of (Z)-diborylalkenes is supported by our theoretical studies.},
  language  = {en}
}
@article{HuangHuKrummenacheretal.2022,
  author    = {Huang, Mingming and Hu, Jiefeng and Krummenacher, Ivo and Friedrich, Alexandra and Braunschweig, Holger and Westcott, Stephen A. and Radius, Udo and Marder, Todd B.},
  title     = {Base-Mediated Radical Borylation of Alkyl Sulfones},
  series = {Chemistry—A European Journal},
  volume    = {28},
  journal   = {Chemistry—A European Journal},
  number    = {3},
  doi       = {10.1002/chem.202103866},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-257281},
  pages     = {e202103866},
  year      = {2022},
  abstract  = {A practical and direct method was developed for the production of versatile alkyl boronate esters via transition metal-free borylation of primary and secondary alkyl sulfones. The key to the success of the strategy is the use of bis(neopentyl glycolato) diboron (B\(_{2}\)neop\(_{2}\)), with a stoichiometric amount of base as a promoter. The practicality and industrial potential of this protocol are highlighted by its wide functional group tolerance, the late-stage modification of complex compounds, no need for further transesterification, and operational simplicity. Radical clock, radical trap experiments, and EPR studies were conducted which show that the borylation process involves radical intermediates.},
  language  = {en}
}