@article {47714,
	title = {Stabilization of the elusive antimony(I) cation and its coordination complexes with transition metals},
	journal = {Angewandte Chemie-International Edition},
	volume = {60},
	year = {2021},
	month = {NOV},
	pages = {25522-25529},
	type = {Article},
	abstract = {Upon stabilization by 5,6-bis(diisopropylphosphino)acenaphthene to form compound 1, the fugitive antimony (I) cation exhibited nucleophilic behavior towards coinage metals. Compound 1 was strategically synthesized at room temperature from SbCl3, the bis(phosphine), and trimethylsilyl trifluoromethanesulfonate taken in a 1:2:3 ratio, whereby the bis(phosphine) plays the dual role of a reductant and a supporting ligand. The generation of 1 involves two-electron oxidation of the ligand to form a P-P bonded diphosphonium dication. Compound 1 was separated from this dication to give both products in pure form in moderate yields. Despite the overall positive charge, the Sb-I site in 1 was found to bind to metal centers, forming complexes with Au-I, Ag-I and Cu-I. Compound 1 reduced Cu-II to Cu-I and formed a coordination complex with the resulting Cu-I species. The effects of the electron-rich bis(phosphine) and the constrained peri geometry in stabilizing and enhancing the nucleophilicity of 1 have been rationalized through computational studies.},
	keywords = {antimony(I) cation, coordination modes, nucleophilicity, phosphine ligands, reduction},
	issn = {1433-7851},
	doi = {10.1002/anie.202111339},
	author = {Kumar, Vikas and Gonnade, Rajesh G. and Yildiz, Cem B. and Majumdar, Moumita}
}
@article {48969,
	title = {Intramolecular donor-stabilized tetra-coordinated germanium(<sc>iv</sc>) di-cations and their Lewis acidic properties},
	journal = {Chemical Science },
	volume = {14},
	year = {2023},
	month = {DEC },
	pages = {13755-13764},
	type = {Article},
	abstract = {<p>
	We report the first examples of intramolecular phosphine-stabilized tetra-coordinated germanium(iv) di-cationic compounds: [(L2Ge)-Ge-iPr][CF3SO3](2)3iPr and [(L2Ge)-Ge-Ph][CF3SO3](2)3Ph (L-iPr = 6-(diisopropylphosphanyl)-1,2-dihydroacenaphthylene-5-ide; L-Ph = 6-(diphenylphosphanyl)-1,2-dihydroacenaphthylene-5-ide). The step wise synthetic strategy involves the isolation of neutral and mono-cationic Ge(iv) precursors: [(L2GeCl)-Ge-iPr][X] (X = GeCl(3)1iPr, OTf 2iPr), [(L2GeCl2)-Ge-Ph] 1Ph and [(L2GeCl)-Ge-Ph][OTf] 2Ph. Both 3iPr and 3Ph exhibit constrained spiro-geometry. DFT studies reveal the dispersion of di-cationic charges over P-Ge-P sites. Anion or Lewis base binding occurs at the Ge site resulting in relaxed distorted trigonal bipyramidal/tetrahedral geometry. 3iPr and 3Ph activate the Si-H bond initially at the P-site. The hydride ultimately migrates to the Ge-site rapidly giving [(L2GeH)-Ge-Ph][CF3SO3] 3PhH, while sluggishly forming [(L2GeH)-Ge-iPr][CF3SO3] 3iPrH. Compounds 3iPr and 3Ph were tested as catalysts for the hydrosilylation of aromatic aldehydes. While catalytic hydrosilylation proceeded via the initial Et3Si-H bond activation in the case of 3iPr, compound 3Ph as a catalyst showed a masked Frustrated Lewis Pair (FLP) type reactivity in the catalytic cycle.</p>
},
	issn = {2041-6520},
	doi = {10.1039/d3sc03717g},
	author = {Peddi, Balakrishna and Khan, Souvik and Gonnade, Rajesh G. and Yildiz, Cem B. and Majumdar, Moumita}
}
