ChemicalBook CAS DataBase List N,N-Dimethylaniline

N,N-Dimethylaniline synthesis

14synthesis methods

Product Name:N,N-Dimethylaniline
CAS Number:121-69-7
Molecular formula:C8H11N
Molecular Weight:121.18

N,N-Dimethylaniline is made by heating aniline, methyl alcohol and sulfuric acid under pressure, followed by hydrolysis of the sulfate formed with sodium hydroxide to the free base (Windholz et al 1983). United States production in 1975 was estimated at 4,600 metric tons (HSDB 1989).

124-38-9
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$214.00/14L

100-61-8 Synthesis

100-61-8
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$8.00/1g

121-69-7
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$10.00/25mL

Yield:121-69-7 99%

Reaction Conditions:

with [Ru(Triphos)(TMM)];hydrogen;1,1,1-trifluoro-N-(trifluoromethylsulfonyl)methanesulfonamide in tetrahydrofuran at 150; under 60006 Torr; for 10 h;Inert atmosphere;Temperature;Time;Reagent/catalyst;Pressure;

Steps:

I

General procedure: General procedures for direct methylation of amines with CO₂/H₂. All high pressure batch experiments were conducted in stainless steel 10 mL autoclaves equipped with a glass inlet and a magnetic stir bar. Prior to use, the autoclave was dried under vacuum for 3 hours and repeatedly filled with argon. Under an argon atmosphere, catalyst [Ru(Triphos)(TMM)] (0.019 g, 0.025 mmol) and HNTf₂ (0.014 g, 0.05 mmol) were weighed in a Schlenk tube. After dissolving in THF (1.0 mL), the mixture was transferred via cannula to the autoclave followed by the addition of the aniline substrate (1.0 mmol) in THF (1.0 mL). The autoclave was then pressurized with CO₂ to 20 bar and then H₂ was added up to a total pressure of 80 bar. The reaction mixture was stirred and heated to 150 °C in an oil bath. After lOh, the autoclave was cooled in an ice bath and then carefully vented. The reaction solution was analyzed by 'H-NMR with internal standard mesitylene and the results confirmed by gas chromatography using dodecane as internal standard. EXAMPLE I: Methylation of N-methylaniline to N,N-Dimethylaniline The reaction was carried out as described above, except where indicated. The results are shown in the following Table I: TABLE I Entry Acid Temp [C°] Time [h] Yield [%] [mol%] 1 - 140 10 2 2 HNTf₂ (0.5) 140 22 11 3 HNTf, (2.5) 140 22 84 4 HNTf, (5), no catalyst added 140 22 0 5 HNTf₂ (5), 1% catalyst used 140 10 50 6 HNTf₂ (5) 140 22 97 7 HNTf₂ (5), 140 22 25 C0₂/H₂: (10/30 bar) 8 HNTf, (5) 120 22 81 9 HNTf, (5) 100 22 58 10 HNTf, (5) 150 0.5 9 11 HNTf, (5) 150 1 20 12 HNTf, (5) 150 1.5 29 13 HNTf, (5) 150 2 34 14 HNTf, (5) 150 3 49 15 HNTf, (5) 150 4 69 16 HNTf, (5) 150 8 97 17 HNTf, (5) 150 10 99 18 MSA (5) 150 10 95 19 / TsOH (5) 150 10 97