Triisobutylaluminium exists in equilibrium with its dimer. The equilibrium constant, KD, is 3.810 at 20 °C.[3]
2Al(CH2CH(CH3)2)3 [Al(CH2CH(CH3)2)3]2
In the dimer, the bridging carbon-aluminium bond is elongated and exhibits evidence of restricted rotation. For the sake of simplicity, TiBA is written as the monomer in this article.
Synthesis
Trialkylaluminium compounds are available industrially through the reactions of aluminium powder, hydrogen gas, and the desired alkenes. The synthesis of TiBA requires two steps; the first step produces diisobutylaluminium hydride (written as a monomer):
6CH2=C(CH3)2 + 2Al + 3H2 → 6HAl(CH2CH(CH3)2)2
In the second step isobutylene adds to the diisobutylaluminium to give TiBA:
α-olefins are readily eliminated from β-branched trialkylaluminium compounds. Trialkylaluminium compounds are used in the industrial production of polymers. In the most common of these compounds, TIBA, a substantial level of Al – H bonds are present at equilibrium. The greater stability of unbranched trialkylaluminium compounds relative to branched trialkylaluminium compounds in TIBA forms the basis for a general synthesis of triethyl- and higher linear trialkylaluminium materials from triisobutylaluminium.
^Michael J. Krause, Frank Orlandi, Alfred T. Saurage, Joseph R. Zietz Jr. "Aluminum Compounds, Organic" in Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. doi:10.1002/14356007.a01_543
^Smith, Martin B. (1970). "The Monomer-Dimer Equilibria of Liquid Ammonium Alkyls II Triisobutylaluminum". Journal of Organometallic Chemistry. 22 (2): 273–281. doi:10.1016/S0022-328X(00)86043-X.
Further reading
Keisuke Suzuki, Tetsuya Nagasaws, Encyclopedia of Reagents for Organic Synthesis, Triisobutylaluminum, 2009
March 08, 2023
triisobutylaluminium, tiba, organoaluminium, compound, with, formula, ch2ch, this, colorless, pyrophoric, liquid, mainly, used, make, linear, primary, alcohols, olefins, monomeric, formnamesiupac, name, triisobutylaluminumother, names, aluminumtriisobutanide, . Triisobutylaluminium TiBA is an organoaluminium compound with the formula Al CH2CH CH3 2 3 This colorless pyrophoric liquid is mainly used to make linear primary alcohols and a olefins 2 Triisobutylaluminium Monomeric formNamesIUPAC name TriisobutylaluminumOther names Aluminumtriisobutanide TIBAIdentifiersCAS Number 100 99 2 Y3D model JSmol Interactive imageECHA InfoCard 100 002 643EC Number 202 906 3PubChem CID 16682931UNII 09P2THV2X4 YUN number 3394 3051CompTox Dashboard EPA DTXSID0026670InChI InChI 1S 3C4H9 Al c3 1 4 2 3 h3 4H 1H2 2 3H3 Key MCULRUJILOGHCJ UHFFFAOYSA NSMILES CC C C Al CC C C CC C CProperties 1 Chemical formula C 12H 27AlMolar mass 198 330 g mol 1Appearance Colorless liquidDensity 0 786 g mL at 25 CMelting point 4 to 6 C 39 to 43 F 277 to 279 K Boiling point 86 C 13 hPa HazardsGHS labelling PictogramsSignal word DangerHazard statements H250 H260 H314Precautionary statements P210 P222 P223 P231 P232 P260 P264 P280 P301 P330 P331 P302 P334 P303 P361 P353 P304 P340 P305 P351 P338 P310 P321 P335 P334 P363 P370 P378 P402 P404 P405 P422 P501Except where otherwise noted data are given for materials in their standard state at 25 C 77 F 100 kPa Y verify what is Y N Infobox references Contents 1 Structure 2 Synthesis 3 Reactions 4 Safety 5 References 6 Further readingStructure EditTriisobutylaluminium exists in equilibrium with its dimer The equilibrium constant KD is 3 810 at 20 C 3 2 Al CH2CH CH3 2 3 displaystyle ce lt gt gt Al CH2CH CH3 2 3 2In the dimer the bridging carbon aluminium bond is elongated and exhibits evidence of restricted rotation For the sake of simplicity TiBA is written as the monomer in this article Synthesis EditTrialkylaluminium compounds are available industrially through the reactions of aluminium powder hydrogen gas and the desired alkenes The synthesis of TiBA requires two steps the first step produces diisobutylaluminium hydride written as a monomer 6 CH2 C CH3 2 2 Al 3 H2 6 HAl CH2CH CH3 2 2In the second step isobutylene adds to the diisobutylaluminium to give TiBA CH2 C CH3 2 HAl CH2CH CH3 2 2 Al CH2CH CH3 2 3Reactions Edita olefins are readily eliminated from b branched trialkylaluminium compounds Trialkylaluminium compounds are used in the industrial production of polymers In the most common of these compounds TIBA a substantial level of Al H bonds are present at equilibrium The greater stability of unbranched trialkylaluminium compounds relative to branched trialkylaluminium compounds in TIBA forms the basis for a general synthesis of triethyl and higher linear trialkylaluminium materials from triisobutylaluminium Al CH2CH CH3 2 3 3 RCH CH2 Al CH2CH2R 3 3 CH2 C CH3 2Safety EditLike most organoaluminium compounds TiBA reacts violently with water and air 1 References Edit a b Sigma Aldrich Triisobutylaluminum MilliporeSigma Merck Group Retrieved 2021 03 15 Michael J Krause Frank Orlandi Alfred T Saurage Joseph R Zietz Jr Aluminum Compounds Organic in Ullmann s Encyclopedia of Industrial Chemistry 2002 Wiley VCH Weinheim doi 10 1002 14356007 a01 543 Smith Martin B 1970 The Monomer Dimer Equilibria of Liquid Ammonium Alkyls II Triisobutylaluminum Journal of Organometallic Chemistry 22 2 273 281 doi 10 1016 S0022 328X 00 86043 X Further reading EditKeisuke Suzuki Tetsuya Nagasaws Encyclopedia of Reagents for Organic Synthesis Triisobutylaluminum 2009 Retrieved from https en wikipedia org w index php title Triisobutylaluminium amp oldid 1118577283, wikipedia, wiki, book, books, library,
