@unpublished{ArrowsmithBoehnkeBraunschweigetal.2017, author = {Arrowsmith, Merle and B{\"o}hnke, Julian and Braunschweig, Holger and Deißenberger, Andrea and Dewhurst, Rian and Ewing, William and H{\"o}rl, Christian and Mies, Jan and Muessig, Jonas}, title = {Simple Solution-Phase Syntheses of Tetrahalodiboranes(4) and their Labile Dimethylsulfide Adducts}, series = {Chemical Communications}, volume = {53}, journal = {Chemical Communications}, doi = {10.1039/C7CC03148C}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-149438}, pages = {8265-8267}, year = {2017}, abstract = {Convenient, solution-phase syntheses of tetrahalodiboranes(4) B\(_2\)F\(_4\), B\(_2\)Cl\(_4\) and B\(_2\)I\(_4\) are presented herein from common precursor B\(_2\)Br\(_4\). In addition, the dimethylsulfide adducts B\(_2\)Cl\(_4\)(SMe\(_2\))\(_2\) and B\(_2\)Br\(_4\)(SMe\(_2\))\(_2\) are conveniently prepared in one-step syntheses from the commercially-available starting material B\(_2\)(NMe\(_2\))\(_4\). The results provide simple access to the full range of tetrahalodiboranes(4) for the exploration of their untapped synthetic potential.}, language = {en} } @article{ArrowsmithBoehnkeBraunschweigetal.2016, author = {Arrowsmith, Merle and B{\"o}hnke, Julian and Braunschweig, Holger and Celik, Mehmet and Dellermann, Theresa and Hammond, Kai}, title = {Uncatalyzed Hydrogenation of First-Row Main Group Multiple Bonds}, series = {Chemistry, A European Journal}, volume = {22}, journal = {Chemistry, A European Journal}, number = {48}, doi = {10.1002/chem.201604094}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-139364}, pages = {17169 -- 17172}, year = {2016}, abstract = {Room temperature hydrogenation of an SIDep-stabilized diboryne (SIDep = 1,3-bis(diethylphenyl)-4,5-dihydroimidazol-2-ylidene) and a CAAC-supported diboracumulene (CAAC = 1-(2,6- diisopropylphenyl)-3,3,5,5-tetramethylpyrrolidin-2-ylidene) provided the first selective route to the corresponding 1,2-dihydrodiborenes. DFT calculations showed an overall exothermic (ΔG = 19.4 kcal mol\(^{-1}\) two-step asynchronous H\(_2\) addition mechanism proceeding via a bridging hydride.}, subject = {Diborane}, language = {en} } @unpublished{ArrowsmithBoehnkeBraunschweigetal.2016, author = {Arrowsmith, Merle and B{\"o}hnke, Julian and Braunschweig, Holger and Celik, Mehmet and Claes, Christina and Ewing, William and Krummenacher, Ivo and Lubitz, Katharina and Schneider, Christoph}, title = {Neutral Diboron Analogues of Archetypal Aromatic Species by Spontaneous Cycloaddition}, doi = {10.1002/anie.201602384}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-142500}, pages = {4}, year = {2016}, abstract = {Among the numerous routes organic chemists have developed to synthesize benzene derivatives and heteroaro- matic compounds, transition-metal-catalyzed cycloaddition reactions are the most elegant. In contrast, cycloaddition reactions of heavier alkene and alkyne analogues, though limited in scope, proceed uncatalyzed. In this work we present the first spontaneous cycloaddition reactions of lighter alkene and alkyne analogues. Selective addition of unactivated alkynes to boron-boron multiple bonds under ambient con- ditions yielded diborocarbon equivalents of simple aromatic hydrocarbons, including the first neutral 6p-aromatic dibora- benzene compound, a 2 p-aromatic triplet biradical 1,3-dibor- ete, and a phosphine-stabilized 2 p-homoaromatic 1,3-dihydro- 1,3-diborete. DFT calculations suggest that all three com- pounds are aromatic and show frontier molecular orbitals matching those of the related aromatic hydrocarbons, C6H6 and C4H42+, and homoaromatic C4H5+.}, subject = {Diborane}, language = {en} } @article{ArrowsmithBoehnkeBraunschweigetal.2016, author = {Arrowsmith, Merle and B{\"o}hnke, Julian and Braunschweig, Holger and Celik, Mehmet and Claes, Christina and Ewing, William and Krummenacher, Ivo and Lubitz, Katharina and Schneider, Christoph}, title = {Neutral Diboron Analogues of Archetypal Aromatic Species by Spontaneous Cycloaddition}, series = {Angewandte Chemie, International Edition}, volume = {55}, journal = {Angewandte Chemie, International Edition}, doi = {10.1002/anie.201602384}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-138226}, pages = {11271-11275}, year = {2016}, abstract = {Among the numerous routes organic chemists have developed to synthesize benzene derivatives and heteroaro- matic compounds, transition-metal-catalyzed cycloaddition reactions are the most elegant. In contrast, cycloaddition reactions of heavier alkene and alkyne analogues, though limited in scope, proceed uncatalyzed. In this work we present the first spontaneous cycloaddition reactions of lighter alkene and alkyne analogues. Selective addition of unactivated alkynes to boron-boron multiple bonds under ambient con- ditions yielded diborocarbon equivalents of simple aromatic hydrocarbons, including the first neutral 6 π-aromatic dibora- benzene compound, a 2  π-aromatic triplet biradical 1,3-dibor- ete, and a phosphine-stabilized 2  π-homoaromatic 1,3-dihydro- 1,3-diborete. DFT calculations suggest that all three com- pounds are aromatic and show frontier molecular orbitals matching those of the related aromatic hydrocarbons, C\(_6\)H\(_6\) and C\(_4\)H\(_4\)\(^{2+}\), and homoaromatic C\(_4\)H\(_5\)\(^+\).}, language = {en} } @unpublished{ArrowsmithBoehnkeBraunschweigetal.2017, author = {Arrowsmith, Merle and B{\"o}hnke, Julian and Braunschweig, Holger and Celik, Mehmet Ali}, title = {Reactivity of a Dihydrodiborene with CO: Coordination, Insertion, Cleavage and Spontaneous Cyclic Alkyne Formation}, series = {Angewandte Chemie, International Edition}, journal = {Angewandte Chemie, International Edition}, doi = {10.1002/anie.201707907}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-153318}, year = {2017}, abstract = {Under a CO atmosphere the dihydrodiborene [(cAAC)HB=BH(cAAC)] underwent coordination of CO concomitant with reversible hydrogen migration from boron to the carbene carbon atom, as well as reversible CO insertion into the B=B bond. Heating of the CO-adduct resulted in two unusual cAAC ring-expansion products, one presenting a B=C bond to a six-membered 1,2-azaborinane-3-ylidene, the other an unprecedented nine-membered cyclic alkyne resulting from reductive cleavage of CO and spontaneous C≡C triple bond formation.}, language = {en} } @unpublished{ArrowsmithBraunschweigStennett2017, author = {Arrowsmith, Merle and Braunschweig, Holger and Stennett, Tom}, title = {Formation and Reactivity of Electron-Precise B-B Single and Multiple Bonds}, series = {Angewandte Chemie, International Edition}, volume = {56}, journal = {Angewandte Chemie, International Edition}, number = {1}, doi = {10.1002/anie.201610072}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-145631}, pages = {96-115}, year = {2017}, abstract = {Recent years have seen rapid advances in the chemistry of small molecules containing electron-precise boron-boron bonds. This review provides an overview of the latest methods for the controlled synthesis of B-B single and multiple bonds as well as the ever-expanding range of reactivity displayed by the latter.}, language = {en} }