95-82-9Relevant articles and documents
Method for synthesizing 2, 5-dichloroaniline by kettle-type continuous hydrogenation
-
Paragraph 0024-0033, (2021/03/13)
The invention provides a method for synthesizing 2, 5-dichloroaniline by kettle-type continuous hydrogenation. The method involves a feeding pump, a preheater, a reactor, a gas-liquid separator and anextraction pump, the feeding pump, the preheater, the reactor, the gas-liquid separator and the extraction pump are sequentially connected in series, and a plurality of hydrogen distribution pipes are arranged in the reactor, a plurality of through holes are formed in the side surface of the hydrogen distribution pipes, and a catalyst is arranged in the hydrogen distribution pipes; the method forsynthesizing 2, 5-dichloroaniline through kettle-type continuous hydrogenation comprises the following steps of: inputting a 2, 5-dichloronitrobenzene solution into the reactor through the feeding pump, inputting hydrogen into the reactor, adsorbing the hydrogen through the catalyst, and then reacting the hydrogen with the 2, 5-dichloronitrobenzene solution to generate 2, 5-dichloroaniline; by adopting the catalyst with high nitro-reduction activity, byproducts are few, and efficient conversion of the raw materials can be realized only at a reaction temperature of 50-80DEG C. By adopting themethod to continuously react for 720 hours, the raw material conversion rate is greater than 95%, and the product selectivity is greater than 95%.
A mild and selective Cu(II) salts-catalyzed reduction of nitro, azo, azoxy, N-aryl hydroxylamine, nitroso, acid halide, ester, and azide compounds using hydrogen surrogacy of sodium borohydride
Kalola, Anirudhdha G.,Prasad, Pratibha,Mokariya, Jaydeep A.,Patel, Manish P.
supporting information, p. 3565 - 3589 (2021/10/12)
The first mild, in situ, single-pot, high-yielding well-screened copper (II) salt-based catalyst system utilizing the hydrogen surrogacy of sodium borohydride for selective hydrogenation of a broad range of nitro substrates into the corresponding amine under habitancy of water or methanol like green solvents have been described. Moreover, this catalytic system can also activate various functional groups for hydride reduction within prompted time, with low catalyst-loading, without any requirement of high pressure or molecular hydrogen supply. Notably, this system explores a great potential to substitute expensive traditional hydrogenation methodologies and thus offers a greener and simple hydrogenative strategy in the field of organic synthesis.
A new process to prepare 3,6-dichloro-2-hydroxybenzoic acid, the penultimate intermediate in the synthesis of herbicide dicamba
Walker, Daniel P.,Harris, G. Davis,Carroll, Jeffery N.,Boehm, Terri L.,McReynolds, Matthew D.,Struble, Justin R.,van Herpt, Jochem,van Zwieten, Don,Koeller, Kevin J.,Bore, Mangesh
, p. 1032 - 1036 (2019/03/17)
Glyphosate [N-(phosphonomethyl)glycine] is a broad spectrum, post-emergent herbicide that is among the most widely used agrochemicals globally. Over the past 30 years, there has been a development of glyphosate-resistant weeds, which pose a significant challenge to growers and crop scientists, resulting in lower crop yields and increased costs. 3,6-Dichloro-2-methoxybenzoic acid (dicamba) is the active ingredient in XtendiMax a standalone herbicide developed by Bayer Crop Science to control broadleaf weeds, including glyphosate-resistant species. 3,6-Dichloro-2-hydroxybenzoic acid (3,6-DCSA) is the penultimate intermediate in the synthesis of dicamba. Existing dicamba manufacturing routes utilize a high temperature, high pressure Kolbe-Schmitt carboxylation to prepare 3,6-DCSA. Described in this Letter is a new, non-Kolbe-Schmitt process to prepare 3,6-DCSA from salicylic acid in four chemical steps.