Nitroethane references:
The titles for these articles are not the actual titles, just brief explanations of the method.
JACS (1954) 76, 4494:
t-butylamine (100g) is added to a solution of KMnO4 (650g) in water (3L) over a period of 15 minutes. The temperature rose to 45*C. The mixture was stirred vigorously for 8 hours after which the heat was raised to 50-60*C for another 8 hours. After the heating is over, the mixture is steam distilled. The product is washed with dilute HCl acid then dH2O. The residue is taken up in a non-polar solvent and dried with MgSO4 and the solvent removed under reduced pressure. The mostly-pure product is then vacuum distilled to give t-nitrobutane (117g, 83% yield). BP: 127-128*C; n28D=1.3980; MP: 25-26*C
(this article also makes mention of basic H2O2 as a possibility for the same reaction)
JACS 9(1956) 78, 4003:
Solvent mix is usually made as 80% acetone and 20% water with the pH being controlled using MgSO4.
258g of t-octylamine (0.2mol) is dissolved in 500ml of acetone. Then 125ml of H2O is added. The mixture is stirred to uniformity. Then, 30g of MgSO4 is added to form a slurry. The suspension must be stirred vigorously for best results. Then, add 190g of KMnO4 over the course of 1 hour. Stir the mixture for 48 hours at 25-30*C and then steam distill the product. The blue colored (as a result of presence of nitroso compounds from side reactions) crude product is taken up in petroleum ether (35-37*C fraction), dried with MgSO4 and then fractionally distilled. The final yield of pure t-nitrooctane is 24.3g (yield 77%). BP: 54*C; n28D= 1.4314
JACS (1957) 79, 5528:
Use of peracetic acid for oxidation of amines to the respective nitro compounds.
CH3COOOH + amine --> Nitro (for aliphatic and aromatics!)
Yields using this procedure from (amine oxidized listed):
Aniline 83%
p-toluidine 72%
o-toluidine 70%
p-anisidine 82%
t-octylamine 87%
cyclohexylamine 70%
sec-butylamine 65%
n-hexylamine* 33%
*the low yield in this instance is reasoned to be a result of isomer/tautomerization of the various intermediates reacting in various ways. This not expected in other primary amines.
Note: The stronger the acid being used to form the per-acid, the greater the need to use a buffer in the form of a base to prevent the adverse effects of full protonation of the amine.
A solution of 60.5ml (0.36mol) trifluoroacetic acid anhydride is placed into a cooled 8.2ml portion of 90% strength H2O2 (0.3mol) in 50ml of DCM. This solution is stirred for 5 minutes and cooled to –25*C. This solution is then added to a suspension of 85g (0.8mol) of Na2CO3 in 400ml of DCM at –25 to –35*C over the course of 30 minutes. Then, add 5.0g (0.005mol) of n-hexylamine in 10 ml of DCM dropwise over another 30 minutes period. While keeping the solution at –30*C, stir the solution mixture for another 30 minutes. The pour the mixture into 500ml of H2O, shake, then separate off the organic layer. The organic layer is then dried with MgSO4 and the solvent is removed. The residue is distilled under reduced pressure to yield 7.9g (80%) n-hexyltrifluroacetic amide*.
*the formation of the amides is unique to the use of per-trifluroacetic acid for the oxidation. If another acid, such as peracetic acid, is used, the nitro compound should be formed.
JOC (1979) 44, 659-661:
General Procedure for the Oxidation of Amines Using m-Chloroperbenzoic acid:
4.1g of m-Chloroperbenzoic acid (0.02mol, 85% purity) is dissolved in 30 ml of solvent in a 3-neck flask fitted with a condensor and a pressure equalized addition funnel. 0.005 mol of the amine to be oxidized is dissolved in 3-5ml of the solvent and is added dropwise to the refluxing peracid solution. The reaction is allowed to take place with refluxing for 0.5-3.0hours. After the reaction time is finished, the solution is cooled and the mix is filtered. Then, the solution is washed 3x50ml of 1 N NaOH and then once more with dH2O to remove traces of NaOH. The solution is dried with MgSO4. The solvent is removed under vacuum and the residue distilled under reduced pressure to give the nitro compound in high enough purity for most applications.
The solvent may be CHCl3, DCM, or DCE in that order with respect to preference according to average yields using said solvents.
JOC (1992) 57, 25, 6759-6764:
General Procedure for the oxidation of amines to their respective nitro compounds using DMDO in a buffered acetone solution:
0.05mol of the amine is placed in a slurry of 10g of NaHCO3, 30ml of H2O, 30ml Acetone and 30ml of DCM. A slurry of DMDO in acetone is added in a very large excess until the amine has been consumed (checked with TLC). The product is extracted from the filtered mixture using ether. The ether is washed with H2O, then brine. After the washings, the ether is dried with MgSO4, the solvent is evaporated and the residue distilled to give the Nitro compound.
The DMDO must be used in large excess to effect the full oxidation to the nitro compound. K2CO3 may be used in place of the NaHCO3 as a buffer.
JOC (1985) 50, 16, 2849:
An oxidation of Pyridine to its oxide is included in the article, but that procedure will be posted in a separate thread.
General Preparation of Oxone/DMDO Slurries:
Oxone (28g, 45 mmol) is placed in acetone (100ml) and stirred at 50*C for 16 hours. The slurry is now ready for use.
Oxidation Potential of the above Slurry:
Aldehydes to acids
Alcohols to Acids
Sulfides to Sulfones
Alkenes to Epoxides
Tetrahedron (1995) 51, 41, 11305-11318:
Preparation of CrS-2 (Chromium silicalite-2):
Gels of composition; SiO2:xCr2O3:0.4TBAOH:30H2O are hydrothermally synthesized by crystallization at 443K for 90 hours followed by calcination at 773K for 5 hours. This gave CrS-2 with a Si:Cr of 140:1.
General Procedure for oxidation of amines w/o phototropic rearrangement:
Aniline (0.93g, 10mmol) is added to CrS-2 (93mg, 10%wt/wt) and 70% TBHP (t-butylhydroperoxide)(4.5ml, 33mmol) in methanol (25ml) and was refluxed for 4 hours. The progress was monitored with TLC. The solution was filtered and then distilled to give nitrobenzene (1.13g, 92% yield). (Works for aliphatics also; 1-aminobutane was oxidized in 80% yield to 1-nitrobutane.)
Tet. Lett. (1981) 22, 18, p 1655-1656:
NaMnO4-H2O in Hexane at 69*C for 24 hours is used to oxidize t-butylamine to t-nitrobutane in 76% yield.
Tet. Lett. Vol 27, No. 21, p 2335-2336 (1986):
Oxidation of n-butylamine using DMDO:
n-butylamine (0.052g, 0.7mmol) in 5 ml of acetone is treated with 95ml of 0.05M DMDO in acetone. The mix is stirred for 30minutes at RT. No light is permitted to enter the reaction for the extent of the oxidation. The mix is filtered, washed with a dilute, weak base. The solvent is dried with MgSO4, then the solvent is removed. The residue is distilled under vacuum to give 87% 1-nitrobutane.
JOC 17 (1952) 906: Vapor-phase nitration of butane w/O2 present
pg 935: Effect of Br2 on Vapor-Phase Nitration of Propane
pg 942: Effect of Cl2 on Vapor-Phase nitration of Propane with HNO3
