2-Nitro-1-propanol preparation

In the improvement of DNPDOH (2,2-dinitro-1,3-propanediol) [66], used sodium nitrite was reduced from 4 times to the equal amount, the amounts of sodium persulfate and potassium ferricyanide were adjusted, which reduced the impact of carbon emission pollution on the environment, and the cost of synthesis was reduced. The synthesis yield was 68 % after improvement, and lower than the production cost is much lower than that of silver nitration method. Major improvement in electrochemical synthesis of DNPOH is that In the first step, sodium hydroxide solution was added to an aqueous solution of 2-nitropropanol after 45 min of stirring at room temperature, lithium perchlorate solution and sodium nitrite solution were added to prepare the deprotonated 2-nitropropanol solution in the second step, deprotonated 2-nitro-propanol solution is added into the working electrode chamber and the reference electrode chamber of the electrolytic cell, and electrolytic reaction is continued for about 1 h under nitrogen for 20 min. Finally DNPOH will be obtained with a yield of about 40 %. The reaction mechanism is ... 

Nitrn-l-propene Preparation is accomphshed by dehydration of l-nitro-2-propanol with methanesuLfonyl chloride and triethylamine (30% ieldi, acetic... 

Notable examples of general synthetic procedures in Volume 47 include the synthesis of aromatic aldehydes (from dichloro-methyl methyl ether), aliphatic aldehydes (from alkyl halides and trimethylamine oxide and by oxidation of alcohols using dimethyl sulfoxide, dicyclohexylcarbodiimide, and pyridinum trifluoro-acetate the latter method is particularly useful since the conditions are so mild), carbethoxycycloalkanones (from sodium hydride, diethyl carbonate, and the cycloalkanone), m-dialkylbenzenes (from the />-isomer by isomerization with hydrogen fluoride and boron trifluoride), and the deamination of amines (by conversion to the nitrosoamide and thermolysis to the ester). Other general methods are represented by the synthesis of 1 J-difluoroolefins (from sodium chlorodifluoroacetate, triphenyl phosphine, and an aldehyde or ketone), the nitration of aromatic rings (with ni-tronium tetrafluoroborate), the reductive methylation of aromatic nitro compounds (with formaldehyde and hydrogen), the synthesis of dialkyl ketones (from carboxylic acids and iron powder), and the preparation of 1-substituted cyclopropanols (from the condensation of a 1,3-dichloro-2-propanol derivative and ethyl-... 

Preparation of 2-nitro-2-methyl-1 -propanol-nitrate. 50g of the 2-nitro-2-methyl-1-propanol purified as above were sifted into a mixt of 58.5g of 90.5% nitric acid.and 241,5g of 103.1% sulfuric acid (oleum) while the well-agitated mixt was maintained close to 15°. Stirring was continued for 1 hour and the mixt allowed to stand for hour. No separation of the nitration product occurred and the mixt was poured over cracked ice. An oily layer separated. The mixt was transferred to a separatory funnel, washed with water, Na bicarbonate, and twice with water to neutrality. The separated diluted spent acid together with the washings were thoroughly extracted with ether, the ether extract washed to neutrality and added to the main product. 

Nitro-l-propene Preparation is accomplished by dehydration of 2-nitro-l-propanol with phthalic anhydride (73%)45 or acetic anhydride-AcONa46 bp 56-57 °C/80 mmHg. 

Two further preparations of 3-nitropropanal 1 have been claimed in the literature by treatment of 1-chloro-3-nitro-2-propanol with potassium hydroxide,5 and by reaction of the 4-isopropyl-2-oxazolin-5-one anion with nitroethene.6 These alternate methods are less suited and less economic for the preparation of 3-nitropropanal 1 on a multigram scale. 

The checkers purchased 2-nitro-l-propanol (ca. 98% purity) from EGA-Aldrich and used it without further purification. The submitters prepared this reagent from nitroethane and formalin according to the procedure of Feuer,2 yield 70-75%, bp 79-80°C (5 mm). 

The procedure described is essentially the same as that of Buck-ley and Scaife.3 The yield has been increased from 55.5% up to 72% by using 1.3 mol eq of phthalic anhydride and by carefully controlling the pressure and cooling the receiving flask. Although 2-nitropropene has previously been prepared by pyrolysis of 2-nitro-1-propyl benzoate in 72% overall yield from 2-nitro-l-propanol,4 the present method is preferred for its preparation since the procedure is much simpler and the product is directly obtainable from 2-nitro-l-propanol without first preparing its ester. It is also applicable to the preparation of 1-nitro-l-propene (58%),5-6 2-nitro-1 -butene (82%),7 and 2-nitro-2-butene (60%).6,7 In general, aliphatic nitroolefins have the tendency to polymerize readily with alkali. 

To the 2-nitro-2-aza-propanol/methylene chloride mixture, prepared in step 1, add 112 grams of methylnitramine. Then add 600 milliliters of 98% sulfuric acid into a suitable flask, and then chill to -10 Celsius by means of an ice bath. Then gradually add the 2-nitro-2-aza-l-propanol/methylene chloride solution in portions to the 98% sulfuric acid while stirring the sulfuric acid and maintaining its temperature below 0 Celsius. After the addition, add the entire reaction mixture into 2000 milliliters of cold water. Then decant the upper methylene chloride layer (keep for later), and then extract the bottom water layer with six, 100-milliliter portions of methylene chloride. Afterwards, combine all the methylene chloride layers (if not already done so), and include the upper methylene chloride layer decanted earlier. Then wash the methylene chloride fraction with two 300 milliliters portions of cold water (in this washing, the methylene chloride layer will be the bottom layer both times). After the 138... 

RC = CCH,X — RCX = C==CH,. /S.y- and 7,S-Acetylenic alcohols can be transformed to the halides in better yields by an alternative procedure, which consists in their esterification with p-toluenesulfonyl chloride and subsequent cleavage of the ester by the action of sodium iodide, lithium chloride, or calcium bromide in an appropriate solvent (60-90%). Halo ethers are prepared by the action of phosphorus tribromide on hydroxy ethers, as in the preparation of /3-ethoxyethyl bromide (66%). In a similar manner, /3-halo esters have been prepared without appreciable dehydration of the /3-hydroxy ester (40-60%). The reaction of cyanohydrins leads to a-halo nitriles. Treatment of 2-nitro-l-propanol with phosphorus pentachloride gives l-chloro-2-nitropropane (47%). ... 

Formylation of amines and alcohols. Behai,8 discoverer of the reagent, found that it reacts unidirectionally with simple alcohols to produce alkyl formates free from acetates. Hurd et al. J found that acetic-formic anhydride (prepared from formic acid and ketene) reacts quantitatively with aniline to give formanilide. Another study10 established that acetic-formic anhydride mixes endothermally with 2-nitro-2-methyl-l-propanol, exothermally with 2-nitro-2-methyl-l,3-propanediol, and displays no appreciable temperature effect with either 2-nitro-l-butanol or tris-(hydroxymethyl)-nitromethane. Formic esters are favored by avoiding a high reaction temperature and by not using sulfuric acid as catalyst. The mixed anhydride has been used for the preparation of formyl fluoride.11... 

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