58471-09-3

Upstream product

• 686-96-4 N-tert-butyltrimethylacetamide 
• 1432-48-0 N-(tert-butyl)-2,2-dimethylpropan-1-imine 
• 33974-41-3 neopentylmagnesium bromide 
• 3282-30-2 pivaloyl chloride 
• 630-19-3 pivalaldehyde 
• 75-64-9 tert-butylamine 

Downstream Products

• 132376-88-6 N-tert-Butyl-N-neopentylbenzamine 
• 132376-91-1 N-tert-Butyl-N-neopentylbenzamide 

Relevant academic research and scientific papers

Cationic Aluminium Complexes as Catalysts for Imine Hydrogenation

Strongly Lewis acidic cationic aluminium complexes, stabilized by β–diketiminate (BDI) ligands and free of Lewis bases, have been prepared as their B(C6F5)4? salts and were investigated for catalytic activity in imine hydrogenation. The backbone (R1) and N (R2) substituents on the R1,R2BDI ligand (R1,R2BDI=HC[C(R1)N(R2)]2) influence sterics and Lewis acidity. Ligand bulk increases along the row Me,DIPPBDIMe,DIPePBDI≈tBu,DIPPBDItBu,DIPePBDI; DIPP=2,6-C(H)Me2-phenyl, DIPeP=2,6-C(H)Et2-phenyl. The Gutmann-Beckett test showed acceptor numbers of: (tBu,DIPPBDI)AlMe+ 85.6, (tBu,DIPePBDI)AlMe+ 85.9, (Me,DIPPBDI)AlMe+ 89.7, (Me,DIPePBDI)AlMe+ 90.8, (Me,DIPPBDI)AlH+ 95.3. Steric and electronic factors need to be balanced for catalytic activity in imine hydrogenation. Open, highly Lewis acidic, cations strongly coordinate imine rendering it inactive as a Frustrated Lewis Pair (FLP). The bulkiest cations do not coordinate imine but its combination is also not an active catalyst. The cation (tBu,DIPPBDI)AlMe+ shows the best catalytic activity for various imines and is also an active catalyst for the Tishchenko reaction of benzaldehyde to benzylbenzoate. DFT calculations on the mechanism of imine hydrogenation catalysed by cationic Al complexes reveal two interconnected catalytic cycles operating in concert. Hydrogen is activated either by FLP reactivity of an Al???imine couple or, after formation of significant quantities of amine, by reaction with an Al???amine couple. The latter autocatalytic Al???amine cycle is energetically favoured.

Alkaline Earth Metal Aluminates as Catalysts for Imine Hydrogenation

Alkaline earth (Ae) metal complexes with the alanate anion AlH4-have been prepared by salt metathesis between NaAlH4and AeCl2in THF and could be isolated as Mg(AlH4)2·(THF)4, Ca(AlH4)2·(THF)4, and Sr(AlH4)2·(THF)5. The previously reported crystal structure of the Mg alanate complex shows bonding of AlH4-with one bridging hydride, H3Al-(μ-H)-Mg, while the Ca and Sr alanates show a combination of H3Al-(μ-H)-Ae and H2Al-(μ-H)2-Ae bridging. The heteroleptic β-diketiminate complexes (DIPPBDI)Mg(AlH4)·THF and (DIPPBDI)Ca(AlH4)·(THF)2have been prepared by reaction of the corresponding Ae hydride complexes with AlH3·(THF)2[DIPPBDI = DIPP-NC(Me)C(H)C(Me)N-DIPP, where DIPP = 2,6-diisopropylphenyl]. Crystal structures show H2Al-(μ-H)2-Ae bridging. The Ca complex decomposes at room temperature by reduction of the β-diketiminate anion. Density functional theory calculations (B3PW91/def2tzvpp) show that the formation of Ae(AlH4)2from AeH2and AlH3is exothermic by δH (kilocalories per mole): Be, -68.8; Mg, -66.1; Ca, -95.4; Sr, -100.9; Ba, -112.3. Calculations of NPA charges on LiAlH4and the Ae alanate complexes (Ae = Mg, Ca, or Sr) show that these are highly ionic salts in which the charge on AlH4-of approximately -0.95 is hardly dependent on the countercation. Compared to LiAlH4, the Ae alanates are very efficient catalysts for imine hydrogenation, clearly extending the substrate scope. In addition to aldimines RC(H)=NR′ (R/R′ = Ph/tBu, tBu/tBu, nPr/tBu, or Ph/Ph), ketimine PhC(Me)=NtBu could be reduced. The salt [Bu4N+][AlH4-] is catalytically not active, which shows that the s-block metal is crucial. The highest activities were found for the heterobimetallic Ca and Sr alanates.

Synthesis of Trialkylamines with Extreme Steric Hindrance and Their Decay by a Hofmann-like Elimination Reaction

A number of amines with three bulky alkyl groups at the nitrogen, which surpass the steric crowding of triisopropylamine considerably, were prepared by using different synthetic methods. It turned out that treatment of N-chlorodialkylamines with organometallic compounds, for example, Grignard reagents, in the presence of a major excess of tetramethylenediamine offered the most effective access to the target compounds. The limits of this method were also tested. The trialkylamines underwent a dealkylation reaction, depending on the degree of steric stress, even at ambient temperature. Because olefins were formed in this transformation, it showed some similarity with the Hofmann elimination. However, the thermal decay of sterically overcrowded tertiary amines was not promoted by bases. Instead, this reaction was strongly accelerated by protic conditions and even by trace amounts of water. Reaction mechanisms, which were analyzed with the help of quantum chemical calculations, are suggested to explain the experimental results.

LiAlH4: From Stoichiometric Reduction to Imine Hydrogenation Catalysis

Imine-to-amine conversion with catalytic instead of stoichiometric quantities of LiAlH4 is demonstrated (85 °C, catalyst loading≥2.5 mol %, pressure≥1 bar). The effects of temperature, pressure, solvent, and catalyst modifications, as well as the substrate scope are discussed. Experimental investigations and preliminary DFT calculations suggest that the catalytically active species is generated in situ: LiAlH4+Ph(H)C=NtBu→LiAlH2[N(tBu)CH2Ph]2. A cooperative mechanism in which Li and Al both play a prominent role is proposed.

A general one-pot, three-component mono N-alkylation of amines and amine derivatives in lithium perchlorate/diethyl ether solution

An efficient, general procedure for reductive monoalkylation of amines and amine derivatives with aldehydes is reported. Treatment of aldehydes with primary amines, secondary amines, O-trimethylsilylhydroxylamine, and N,N-dimethylhydrazine in lithium perc

Clefts in Simple Acyclic Organic Molecules. Correlated Stereodynamics of N-tert-Alkylbenzylamines Studied by Dynamic NMR Spectroscopy, X-ray Diffraction, and Molecular Mechanics Calculations

In N-tert-butyl-N-neopentylbenzylamine (1), the slowing of four processes can be observed in the NMR spectrum at low temperature.The rate constant for 120 deg rotation of the N-tert-butyl group is three times that for 180 deg rotation of the phenyl group

Configurational Prevalence at the Nitrogen Atom in Chiral, Open Chain, Secondary Amines

The stereochemistry of chiral, open chain, secondary amines has been studied by means of low-temperature (1)H and (13)C n.m.r. spectroscopy and by PCILO molecular-orbital calculations.The chiral nitrogen assumes a strongly prevalent configuration under the assymmetric induction of a vicinal asymmetric carbon atom.In the most probable conformation of the secondary amine the lone pair of the nitrogen is placed in the most crowded position.