%0 Journal Article %1 Magnall2019 %A Magnall, Rosie %A Balázs, Gábor %A Lu, Erli %A Kern, Michal %A van Slageren, Joris %A Tuna, Floriana %A Wooles, Ashley J. %A Scheer, Manfred %A Liddle, Stephen T. %D 2019 %J Chemistry - A European Journal %K from:michalkern myown %N 62 %P 14246--14252 %R 10.1002/chem.201903973 %T Photolytic and Reductive Activations of 2-Arsaethynolate in a Uranium–Triamidoamine Complex: Decarbonylative Arsenic-Group Transfer Reactions and Trapping of a Highly Bent and Reduced Form %V 25 %X Little is known about the chemistry of the 2-arsaethynolate anion, but to date it has exclusively undergone fragmentation reactions when reduced. Herein, we report the synthesis of [U(TrenTIPS)(OCAs)] (2, TrenTIPS=N(CH2CH2NSiiPr3)3), which is the first isolable actinide-2-arsaethynolate linkage. UV-photolysis of 2 results in decarbonylation, but the putative [U(TrenTIPS)(As)] product was not isolated and instead only [\U(TrenTIPS)\2($\mu$-$\eta$2:$\eta$2-As2H2)] (3) was formed. In contrast, reduction of 2 with [U(TrenTIPS)] gave the mixed-valence arsenido [\U(TrenTIPS)\2($\mu$-As)] (4) in very low yield. Complex 4 is unstable which precluded full characterisation, but these photolytic and reductive reactions testify to the tendency of 2-arsaethynolate to fragment with CO release and As transfer. However, addition of 2 to an electride mixture of potassium-graphite and 2,2,2-cryptand gives [\U(TrenTIPS)\2\$\mu$-$\eta$2(OAs):$\eta$2(CAs)-OCAs\][K(2,2,2-cryptand)] (5). The coordination mode of the trapped 2-arsaethynolate in 5 is unique, and derives from a new highly reduced and bent form of this ligand with the most acute O-C-As angle in any complex to date (O-C-As \textless ≈128°). The trapping rather than fragmentation of this highly reduced O-C-As unit is unprecedented, and quantum chemical calculations reveal that reduction confers donor–acceptor character to the O-C-As unit.

@article{Magnall2019, abstract = {Little is known about the chemistry of the 2-arsaethynolate anion, but to date it has exclusively undergone fragmentation reactions when reduced. Herein, we report the synthesis of [U(TrenTIPS)(OCAs)] (2, TrenTIPS=N(CH2CH2NSiiPr3)3), which is the first isolable actinide-2-arsaethynolate linkage. UV-photolysis of 2 results in decarbonylation, but the putative [U(TrenTIPS)(As)] product was not isolated and instead only [{\{}U(TrenTIPS){\}}2($\mu$-$\eta$2:$\eta$2-As2H2)] (3) was formed. In contrast, reduction of 2 with [U(TrenTIPS)] gave the mixed-valence arsenido [{\{}U(TrenTIPS){\}}2($\mu$-As)] (4) in very low yield. Complex 4 is unstable which precluded full characterisation, but these photolytic and reductive reactions testify to the tendency of 2-arsaethynolate to fragment with CO release and As transfer. However, addition of 2 to an electride mixture of potassium-graphite and 2,2,2-cryptand gives [{\{}U(TrenTIPS){\}}2{\{}$\mu$-$\eta$2(OAs):$\eta$2(CAs)-OCAs{\}}][K(2,2,2-cryptand)] (5). The coordination mode of the trapped 2-arsaethynolate in 5 is unique, and derives from a new highly reduced and bent form of this ligand with the most acute O-C-As angle in any complex to date (O-C-As {\textless} ≈128°). The trapping rather than fragmentation of this highly reduced O-C-As unit is unprecedented, and quantum chemical calculations reveal that reduction confers donor–acceptor character to the O-C-As unit.}, added-at = {2020-10-12T12:53:11.000+0200}, author = {Magnall, Rosie and Bal{\'{a}}zs, G{\'{a}}bor and Lu, Erli and Kern, Michal and van Slageren, Joris and Tuna, Floriana and Wooles, Ashley J. and Scheer, Manfred and Liddle, Stephen T.}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2f42dc2c5df0d6e318dcb512f3d7e9bb9/iis}, doi = {10.1002/chem.201903973}, file = {:C$\backslash$:/Users/iismike/Downloads/chem.201903973.pdf:pdf}, interhash = {32e875965c5e3aa5dd4dee3caebd6e03}, intrahash = {f42dc2c5df0d6e318dcb512f3d7e9bb9}, issn = {15213765}, journal = {Chemistry - A European Journal}, keywords = {from:michalkern myown}, number = 62, pages = {14246--14252}, pmid = {31478589}, timestamp = {2020-10-12T10:53:11.000+0200}, title = {Photolytic and Reductive Activations of 2-Arsaethynolate in a Uranium–Triamidoamine Complex: Decarbonylative Arsenic-Group Transfer Reactions and Trapping of a Highly Bent and Reduced Form}, volume = 25, year = 2019 }