(Trimethylsilyl)methyllithium

TmsLi.svg 1822-00-0 2723465 629-440-7 3482579 1S/C4H11Si.Li/c1-5(2,3)4;/h1H2,2-4H3;/q-1;+1 KVWLUDFGXDFFON-UHFFFAOYSA-N [Li+].C[Si](C)(C)[CH2-] 4 11 1 1 white or colorless solid 0.937 g/cm3 (Trimethylsilyl)methyllithium https://pubchem.ncbi.nlm.nih.gov/compound/3482579#section=Safety-and-Hazards pubchem.ncbi.nlm.nih.gov 12 January 2022 en 02 05 Danger 225 314 210 233 240 241 242 243 260 264 280 301+330+331 303+361+353 304+340 305+351+338 310 321 363 370+378 403+235 405 501 (Trimethylsilyl)methyllithium is classified both as an organolithium compound and an organosilicon compound. It has the empirical formula LiCH2Si(CH3)3, often abbreviated LiCH2TMS. It crystallizes as the hexagonal prismatic hexamer [LiCH2TMS]6, akin to some polymorphs of methyllithium.10.1016/0022-328X(86)80537-X X-ray Crystal Structure of Trimethylsilylmethyllithium 1986 Tecle' Berhan Maqsudur Rahman A.F.M. Oliver John P. Journal of Organometallic Chemistry 317 3 267–275 Many adducts have been characterized including the diethyl ether complexed cubane [Li4(μ3-CH2TMS)4(Et2O)2]10.1039/c002504f The First Asymmetric Organolithium Tetramers with Simple Ether Donor Bases 2010 Tatic Tanja Meindl Kathrin Henn Julian Pandey Sushil Kumar Stalke Dietmar Chemical Communications 46 25 4562–4564 20502820 and [Li2(μ-CH2TMS)2(TMEDA)2].10.1002/ejic.200800610 Deaggregation of Trimethylsilylmethyllithium 2008 Tatic Tanja Ott Holger Stalke Dietmar European Journal of Inorganic Chemistry 2008 24 3765–3768 2008EJIC.2008.3765T Preparation (Trimethylsilyl)methyllithium, which is commercially available as a THF solution, is usually prepared by treatment of (trimethylsilyl)methyl chloride with butyllithium:2019 Trimethylsilylmethyllithium Encyclopedia of Reagents for Organic Synthesis 10.1002/047084289X.rt321 Werth Jacob David J. Age 978-0471936237 (CH3)3SiCH2Cl + BuLi → (CH3)3SiCH2Li + BuCl (Trimethylsilyl)methylmagnesium chloride is often functionally equivalent to (trimethylsilyl)methyllithium. It is prepared by the Grignard reaction of (trimethylsilyl)methyl chloride.10.1002/9780470132562.ch15 1989 Inorganic Syntheses 2007 Brennan David J. Graaskamp James M. Dunn Beverly S. Allcock Harry R. Organosilicon Derivatives of Cyclic and High Polymeric Phosphazenes 25 60–68 9780470132562Takayuki Shioiri Toyohik Aoyama Shigehiro Mori Trimethylsilyldiazomethane 68 1 1990 10.15227/orgsyn.068.0001 Use in methylenations In one example of the Peterson olefination, (trimethylsilyl)methyllithium reacts with aldehydes and ketones to give the terminal alkene (R1 = Me, R2 & R3 = H): 380px|The Peterson olefination Metal derivatives thumb|234px|left|Structure of the organoscandium complex with two (trimethylsilyl)methyl ligands, (C5H5)Sc(CH2TMS)2(THF).10.1021/ja9056213 Alternating and Random Copolymerization of Isoprene and Ethylene Catalyzed by Cationic Half-Sandwich Scandium Alkyls 2009 Li Xiaofang Nishiura Masayoshi Hu Lihong Mori Kyouichi Hou Zhaomin Journal of the American Chemical Society 131 38 13870–13882 19728718 2009JAChS.13113870L Color scheme: O (red), Sc (blue), Si (orange). (Trimethylsilyl)methyllithium is widely used in organotransition metal chemistry to affix (trimethylsilyl)methyl ligands. Such complexes are usually produced by salt metathesis involving metal chlorides. These compounds are often highly soluble in nonpolar organic solvents, enjoying stability due to their steric bulk and resistance to beta-hydride elimination. In these regards, (trimethylsilyl)methyl is akin to neopentyl. Bis(trimethylsilyl)methylmagnesium is used as an alternative to (trimethylsilyl)methyllithium. Richard A. Andersen, Geoffrey Wilkinson Inorganic Syntheses Bis[(Trimethylsilyl)Methyl] Magnesium 10.1002/9780470132500.ch61 1979 19 262–265 9780470132500 Related compounds bis(trimethylsilyl)methyllithium10.1039/C39840001163 Molecular structures of Bis(trimethylsilyl)methyl-lithium [(LiR), R = CH(SiMe3)2] in the Vapour (Gas-Phase Electron Diffraction: a Monomer, n= 1) and the Crystal (X-ray: a Polymer, n=∞) Journal of the Chemical Society, Chemical Communications 1984 1163–1165 Jerry L. Atwood Torgny Fjeldberg Michael F. Lappert N. Tuyet Luong-Thi Riz Shakir Andrew J. Thorne 17 tris(trimethylsilyl)methyllithium10.1039/C39830000827 Crystal structure of the Tetrahydrofuran Adduct of Tris(trimethylsilyl)-Methyl-Lithium, [Li(thf)4][Li{C(SiMe3)3}2], an Ate Derivative of Lithium Journal of the Chemical Society, Chemical Communications Colin Eaborn Peter B. Hitchcock J. David Smith Alice C. Sullivan 1983 827–828 References Category:Organolithium compounds Category:Trimethylsilyl compounds