29617-66-1Relevant articles and documents
Optimization of the use of a chiral bio-based building block for the manufacture of DHPPA, a key intermediate for propionate herbicides
Fleer, Michel P. M.,Verkuijl, Bastiaan J. V.
, p. 3993 - 3998 (2014)
An alternative route for the production of (R)-2-(4-hydroxyphenoxy) propionic acid (DHPPA), a key intermediate in herbicide chemistry, is proposed. This route makes use of a chiral building block, initially produced by fermentation. The route has been optimized based on two steps: chlorination and etherification. The chlorination step has a maximum ee of 99% and a yield of 85% after distillation. The etherification step has a yield of 66%. Comparison of the route with the industrial standard shows a significant improvement in terms of green chemistry: waste streams are lowered up to 7-fold and the toxicity of the waste streams is reduced. This journal is the Partner Organisations 2014.
Asymmetric reduction of 2-chloroacrylic acid to (S)-2-chloropropionic acid by a novel reductase from Burkholderia sp. WS
Kurata, Atsushi,Kurihara, Tatsuo,Kamachi, Harumi,Esaki, Nobuyoshi
, p. 2837 - 2839 (2004)
Burkholderia sp. WS has a novel enzyme that catalyzes the asymmetric reduction of 2-chloroacrylic acid to yield (S)-2-chloropropionic acid, which is used as a building block for the synthesis of aryloxyphenoxypropionic acid herbicides. NADPH is required as a co-substrate for this reaction.
A facile microwave assisted synthesis and structure elucidation of (3R)-3-alkyl-4,1-benzoxazepine-2,5-diones by crystallographic, spectroscopic and DFT studies
Raza, Abdul Rauf,Nisar, Bushra,Khalid, Muhammad,Gondal, Humaira Yasmeen,Khan, Muhammad Usman,de Alcantara Morais, Sara Figueirêdo,Tahir, Muhammad Nawaz,Braga, Ataualpa Albert Carmo
, (2020/01/21)
The use of microwave (MW) irradiation in organic synthesis has become increasingly popular within the pharmaceutical and academic arenas because it is a new enabling technology for drug discovery and development. It is a rapid way of synthesis, which involves faster reaction rates and high selectivity to conventional heating method of syntheses. The MW-assisted 7-exo-tet cyclization of N-acylanthranilic acids afforded (3R)-3-alkyl-4,1-benzoxazepines-2,5-diones in very short duration (20 min) with extraordinary high yields in comparison to conventional heating mode of synthesis. The method development, comparative yields of MW-assisted and thermal method of syntheses, crystallographic, spectroscopic and density functional theory (DFT) studies are reported herein. Four novel compounds with chemical formulas C10H9BrClNO3 5m, C19H19NO3 6e, C13H14ClNO3 6h and C12H11Br2NO3 6h were synthesized, validated by 1HNMR, 13CNMR, FT-IR, UVVis, EIMS spectroscopic techniques and confirmed by using single crystal X-ray diffraction (SC-XRD) study. The DFT and TDDFT calculations at B3LYP/6-311 + G(d,p) level of theory were performed for comparative analysis of spectroscopic data, optimized geometries, frontier molecular orbitals (FMOs), natural bond orbital (NBO) analysis and nonlinear optical (NLO) properties of 5m, 6e, 6h and 6o. Overall, experimental findings were supported nicely by corresponding DFT computed results. The NBO analysis confirmed that the presence of non-covalent interactions, hydrogen bonding and hyper- conjugative interactions are pivotal cause for the existence of 5m, 6e, 6h and 6o in the solid-state. NLO analysis showed that 5m, 6e, 6h and 6o have significant NLO properties as compared to prototype standard compound which disclosed their potential for technology related applications.
Synthetic method of high-purity and high-yield L-2-chloropropionic acid
-
Paragraph 0021; 0023; 0025; 0027; 0029, (2018/04/26)
The invention discloses a synthetic method of L-2-chloropropionic acid. The synthetic method comprises the steps of firstly dissolving L-alanine into hydrochloric acid, introducing nitrosyl chloride and hydrogen chloride gas for reaction, after the raw materials are converted, filtering, continuing to stir for 1-2 hours, and an alkaline reagent for neutralization, extracting by virtue of an organic solvent, combining organic phases, drying by virtue of anhydrous calcium chloride, filtering, and carrying out rectification, so as to obtain a product, namely L-2-chloropropionic acid. The method has the advantages that the operation is simple, and the emission of wastewater is reduced; and by taking nitrosyl chloride with relatively high activity as a diazotization regent, aliphatic amino canbe rapidly converted into chlorine, so that the raw material conversation rate and the yield are greatly increased, the yield can reach 90% or above, an original configuration is not reversed in the reaction process, and the optical purity ee value can reach 99.1%.
Di(1-naphthyl) methanol ester of carboxylic acids for absolute stereochemical determination
Zhang, Jun,Sheng, Wei,Gholami, Hadi,Nehira, Tatsuo,Borhan, Babak
supporting information, p. 141 - 146 (2017/11/13)
The absolute stereochemistry of chiral carboxylic acids is determined as a di(1-naphthyl)methanol ester derivative. Computational scoring of conformations favoring either P or M helicity of the naphthyl groups, capable of exciton-coupled circular dichroic coupling, leads to a predicted stereochemistry for the derivatized carboxylic acids.