背景介紹
雙(三甲基硅基)氨基鋰(LiHMDS)又叫六甲基二硅基氨基鋰。可用于制備低配位數(shù)的金屬配合物,因?yàn)榕潴w的位阻很大。在有機(jī)合成或藥物合成中,雙(三甲基硅基)氨基鋰通常用作非親核性強(qiáng)堿,與其他大位阻有機(jī)強(qiáng)堿,如二異丙基氨基鋰,雙三甲基硅基氨基鉀,雙三甲基硅基氨基鈉等等相比,作用類(lèi)似,但堿性更強(qiáng),在某些反應(yīng)中有其獨(dú)特的地方,有其他有機(jī)堿不具備的優(yōu)勢(shì)。
合成工藝
一種是在惰性氣體保護(hù)下,采用正丁基鋰或氫化鋰或氨基鋰奪取六甲基二硅胺烷的質(zhì)子,利用無(wú)水無(wú)氧的有機(jī)溶劑做反應(yīng)溶劑,低溫反應(yīng)。另一種方式是采用金屬鋰和六甲基二硅胺烷高溫反應(yīng),同時(shí)使用三氯化鐵作為催化劑,反應(yīng)完全后,再用四氫呋喃溶劑溶解,制得六甲基二硅烷胺鋰四氫呋喃溶液。還有一種是惰性氣體保護(hù)下,向反應(yīng)容器中加入金屬鋰、異戊二烯、六甲基二硅氮烷和四氫呋喃,經(jīng)一步合成反應(yīng)得到最終產(chǎn)品。
應(yīng)用實(shí)例
1.文章報(bào)道利用LiHMDS和三氟甲磺酸酐一步法將酰胺脫氫轉(zhuǎn)化為烯酰胺,其中LiHMDS和磺酸酐添加順序至關(guān)重要,需要先添加LiHMDS,否則產(chǎn)率由92%下降至52%。反應(yīng)機(jī)理利用氘代實(shí)驗(yàn)證明,首先三氟甲磺酸酐將酰胺活化從而使N的α-氫酸化,之后發(fā)生去質(zhì)子化和消除得到烯酰胺產(chǎn)物[1]。


圖片來(lái)源于期刊:Journal of the American Chemical Society, 2021, 143, 10524-10529.
2.環(huán)狀聚合物具有獨(dú)特的物理化學(xué)和生物特性,但是合成具有很大的挑戰(zhàn)性。該文章研發(fā)出利用LiHMDS促進(jìn)環(huán)膨脹聚合的簡(jiǎn)單途徑,從N-烷基-N羧酸酐(NNCA)合成具有生物活性的大環(huán)[2]。


圖片來(lái)源于期刊:Journal of the American Chemical Society 2021, 143, 3697-3702.
參考文獻(xiàn):
[1] Journal of the American Chemical Society, 2021, 143, 10524-10529.
[2] Journal of the American Chemical Society 2021, 143, 3697-3702.
| Chemical Name | Lithium bis(trimethylsilyl)amide |
|---|---|
| CAS Number | 4039-32-1 |
| EC Number | 223-725-6 |
| Beilstein Registry Number | 3567910 |
| MDL Number | MFCD00008261 |
| Synonym | (LiN(SiMe3)2) Li bis(TMS)A Lithium Bis(trimethylsilyl)amide (ca. 26% in Tetrahydrofuran, ca. 1.3mol/L) {} {} {} {} {} {} {} {} {} {} {} {} {} {PubChem} lithium bis(trimethylsilyl)amide {} {} {} {} {} {} {} {} {LY} Lithium bis(trimethylsilyl)amine,1.0M solution in THF,Safeseal {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {LY} Lithium bis(trimethylsilyl)amine,1.0M solution in THF,Safeseal {} {} {} {} {} {} {} {} {} {} {} {LY} Lithium bis(trimethylsilyl)amine,1.0M solution in THF,Safeseal {} {} {} {} {} {} {} {} {} {} {} {} {LY} Lithium bis(trimethylsilyl)amine,1.0M solution in THF,Safeseal {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {LY} Lithium bis(trimethylsilyl)amine,1.0M solution in THF,Safeseal {} {} {} {} {} {} {} {} {} {} {} {} {} {} {LY} Lithium bis(trimethylsilyl)amine,1.0M solution in THF,Safeseal {} {} {} {} { |
| PubChem Substance ID | 2733832 |
| Reaxys-RN | 8136861 |
| Chemical Name Translation | 雙(三甲基硅基)氨基鋰 |
| InChIKey | YNESATAKKCNGOF-UHFFFAOYSA-N |
| LabNetwork Molecule ID | LN00162852 |
| InChI | InChI=1S/C6H18NSi2.Li/c1-8(2,3)7-9(4,5)6;/h1-6H3;/q-1;+1 |
| Canonical SMILES | C[Si]([N-][Si](C)(C)C)(C)C.[Li+] |
| Signal word | Danger |
|---|---|
| WGK Germany | 3 |
| Safety Statements | |
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| Risk Statements | |
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| Hazard statements | |
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| Personal Protective Equipment | Eyeshields, Faceshields, full-face particle respirator type N100 (US), Gloves, respirator cartridge type N100 (US), type P1 (EN143) respirator filter, type P3 (EN 143) respirator cartridges Faceshields, full-face respirator (US), Gloves, Goggles, multi-purpose combination respirator cartridge (US) Faceshields, full-face respirator (US), Gloves, Goggles, multi-purpose combination respirator cartridge (US), type ABEK (EN14387) respirator filter |
| Packing Group | II |
| UN Number | 2924 UN2924 |
| Storage condition | 2-8°C, sealed storage, away from moisture 87.0 below 5° C {} {} {} {} {} {} { {} {} {} {} {} {} {} { {} {} {} {} {} {} {} {} { {} {} {} {} {} {} {} {} {} {LY} 2-8°C, sealed storage, away from moisture {} {} {} {} {} {} {} {} {} {} {LY} 2-8°C, sealed storage, away from moisture {} {} {} {} {} {} {} {} {} {} {} {LY} 2-8°C, sealed storage, away from moisture {} {} {} {} {} {} {} {} {} {} {} {} {LY} 2-8°C, sealed storage, away from moisture {} {} {} {} {} {} {} {} {} {} {} {} {} {LY} 2-8°C, sealed storage, away from moisture {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {LY} 2-8°C, sealed storage, away from moisture {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {LY} 2-8°C, sealed storage, away from moisture {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {LY} 2-8°C, sealed storage, away from moisture {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {LY} 2-8°C, sealed storage, away from moisture {} {} {} {} {} { |
| Hazard Codes | 3 F,C |
| Hazard Class | 3/8 |
| Restrict | - |
| Mol. Formula | C6H18LiNSi2 |
|---|---|
| Mol. Weight | 167.33 |
| Density | 0.87 |
| Boiling Point | 55 - 56 °C |
| Flash Point | -17 °C - (閉杯) |
| TSCA | Yes |
| Melting Point | 70 - 76 °C |
| Solubility | 水解 |
| Refractive index | n20/D 1.425(lit.) |
| Stability | 對(duì)空氣和濕度敏感 |
| Danger-Level | 甲類(lèi) |
| pH | -:- |
| Redox | - |
*以上化合物性質(zhì)及應(yīng)用等信息僅供參考