1818-22-0Relevant academic research and scientific papers
Continuous Platform to Generate Nitroalkanes On-Demand (in Situ) Using Peracetic Acid-Mediated Oxidation in a PFA Pipes-in-Series Reactor
Tsukanov, Sergey V.,Johnson, Martin D.,May, Scott A.,Kolis, Stanley P.,Yates, Matthew H.,Johnston, Jeffrey N.
supporting information, p. 971 - 977 (2018/08/28)
The synthetic utility of the aza-Henry reaction can be diminished on scale by potential hazards associated with the use of peracid to prepare nitroalkane substrates and the nitroalkanes themselves. In response, a continuous and scalable chemistry platform to prepare aliphatic nitroalkanes on-demand using the oxidation of oximes with peracetic acid and direct reaction of the nitroalkane intermediate in an aza-Henry reaction is reported. A uniquely designed pipes-in-series plug-flow tube reactor addresses a range of process challenges, including stability and safe handling of peroxides and nitroalkanes. The subsequent continuous extraction generates a solution of purified nitroalkane, which can be directly used in the following enantioselective aza-Henry chemistry to furnish valuable chiral diamine precursors with high selectivity, thus completely avoiding isolation of the potentially unsafe low-molecular-weight nitroalkane intermediate. A continuous campaign (16 h) established that these conditions were effective in processing 100 g of the oxime and furnishing 1.4 L of nitroalkane solution.
Scalable, easy synthesis, and efficient isolation of arylnitromethanes: a revival of the Victor Meyer reaction
Alaime, Thibaud,Delots, Audrey,Pasquinet, Eric,Suzenet, Franck,Guillaumet, Gérald
, p. 1337 - 1341 (2017/01/21)
A modified approach to synthesize and isolate arylnitromethanes is described. The method takes advantage of the significant difference in acidity between the arylnitromethane and the major impurity of the reaction, the nitrite ester. The arylnitromethanes resulting from this process are obtained in high yields and are analytically pure, i.e., they do not require distillation or further purification, which is a comfortable improvement of the ancestral Victor Meyer reaction.
Minimizing the amount of nitromethane in palladium-catalyzed cross-coupling with aryl halides
Walvoord, Ryan R.,Kozlowski, Marisa C.
, p. 8859 - 8864 (2013/09/24)
A method for the formation of arylnitromethanes is described that employs readily available aryl halides or triflates and small amounts of nitromethane in a dioxane solvent, thereby reducing the hazards associated with this reagent. Specifically, 2-10 equiv (1-5% v/v) of nitromethane can be employed in comparison to prior work that used nitromethane as solvent (185 equiv). The present transformation provides high yields at relatively low temperatures and tolerates an array of functionality, including heterocycles and substantial steric encumbrance.
Palladium-catalyzed nitromethylation of aryl halides: An orthogonal formylation equivalent
Walvoord, Ryan R.,Berritt, Simon,Kozlowski, Marisa C.
supporting information; experimental part, p. 4086 - 4089 (2012/09/22)
An efficient cross-coupling reaction of aryl halides and nitromethane was developed with the use of parallel microscale experimentation. The arylnitromethane products are precursors for numerous useful synthetic products. An efficient method for their direct conversion to the corresponding oximes and aldehydes in a one-pot operation has been discovered. The process exploits inexpensive nitromethane as a carbonyl equivalent, providing a mild and convenient formylation method that is compatible with many functional groups.
Ozone-mediated Nitration of Alkylbenzenes and Related Compounds with Nitrogen Dioxide
Suzuki, Hitomi,Murashima, Takashi,Kozai, Iku,Mori, Tadashi
, p. 1591 - 1598 (2007/10/02)
In the presence of ozone, nitrogen dioxide exhibits a strong nitrating ability for alkylbenzenes at low temperatures, converting them into the corresponding nitro derivatives in high yield.The addition of a protonic acid as catalyst enhances considerably the ability of this nitrating system and leads to a good yield of polynitro compounds.The reaction is clean and proceeds rapidly without any accompanying side-chain substitution or aryl-aryl coupling.It shows no kinetic dependence on the concentration of substrates and, as far as can be judged from relative reactivities and isomer distributions of products, it gives the appearance of being an electrophilic aromatic process.A possible role for nitrogen trioxide has been suggested as the initial electrophilic agent for the nitration of alkylbenzenes.
Cyclopentadienyliron-mediated introduction of functionalized alkyl or alkynyl groups to arenes in an addition-demetallation sequence
Sutherland, Ronald G.,Zhang, Chunhao,Piorko, Adam
, p. 357 - 373 (2007/10/02)
Nitromethyl, cyanomethyl, and phenylethynyl anions add selectively ortho to arenes containing electron-withdrawing groups and complexed with cyclopentadienyliron.Under similar reaction conditions anions such as alkyl, dichloromethyl and trichloromethyl add in a non-selective way.Addition of the trichloromethyl anion is thermodynamically controlled at extended reaction times and, due to the size of the anion, the meta addition is favoured.Demetallation of adducts leads to ortho-nitromethylated, cyanomethylated or phenylethynylated arenes, respectively.With symmetrical arene complexes the addition-demetallation sequence leads to the introduction of a trichloromethyl group into the arene ring, yielding a single product.A one-pot procedure for trichloromethylation of dialkylarenes starting from appropriate cyclopentadienyliron complexes gives β-trichloromethylated dialkylarenes in a good yield.
