Defluorinative [4 + 1] annulation of perfluoroalkyl <i>N</i>-mesylhydrazones with primary amines provides 5-fluoroalkyl 1,2,3-triazoles
作者:Yongquan Ning、Hongwei Wang、Paramasivam Sivaguru、Shuang Li、Giuseppe Zanoni、Steven P. Nolan、Xihe Bi
DOI:10.1039/d1gc02749b
日期:——
blocks. However, only a few synthetic routes to these compounds are currently available. Herein, we report on a novel method to access 5-fluoroalkyl 1,2,3-triazoles from easily prepared bench-stable perfluoroalkyl N-mesylhydrazone (PFHZ-Ms), a reagent that can transform amines to 5 fluoroalkyl 1,2,3-triazoles via defluorinative [4 + 1] annulation. The simple reaction protocol can be applied to a variety
Asymmetric synthesis of quaternary α-fluoro-β-keto-amines via detrifluoroacetylative Mannich reactions
作者:Chen Xie、Yanling Dai、Haibo Mei、Jianlin Han、Vadim A. Soloshonok、Yi Pan
DOI:10.1039/c5cc02256h
日期:——
Asymmetric detrifluoroacetylative Mannich reactions of N-sulfinyl-imines via C–C bond cleavage were explored, which provide access to C–F quaternary α-fluoro-β-keto-amines.
[EN] PERFLUORINATED POLYOLS AND THEIR USE FOR THE ENANTIOMERIC SEPARATION OF CHIRAL ANIONS<br/>[FR] POLYOLS PERFLUORÉS ET LEUR UTILISATION POUR LA SÉPARATION ÉNANTIOMÉRIQUE D'ANIONS CHIRAUX
申请人:CENTRE NAT RECH SCIENT
公开号:WO2020260437A1
公开(公告)日:2020-12-30
The invention relates to perfluorinated polyols and their use for enantiomeric separation of chiral anions. It also relates to a process for preparing such perfluorinated polyols, and to a process for the enantiomeric separation of chiral anions.
The UV and IR spectra of CxF2x+1CHO (x = 1–4) were investigated using computational and experimental techniques. CxF2x+1CHO (x = 1–4) have broad UV absorption features centered at 300–310 nm. The maximum absorption cross-section increases significantly and shifts slightly to the red with increased length of the CxF2x+1 group: CF3CHO, 3.10 × 10−20 (300 nm); C2F5CHO, 6.25 × 10−20 (308 nm); C3F7CHO, 8
使用计算和实验技术研究了C x F 2 x +1 CHO(x = 1-4)的紫外和红外光谱。C x F 2 x +1 CHO(x = 1-4)具有在300-310 nm处集中的宽紫外线吸收功能。随着C x F 2 x +1基团长度的增加,最大吸收截面显着增加,并向红色略微偏移:CF 3 CHO,3.10×10 -20(300 nm); C 2 F 5 CHO,6.25×10 -20(308nm);m / z。C 3 F7 CHO,8.96×10 -20(309 nm); 和C 4 F 9 CHO,10.9×10 -20(309nm)。记录,计算和分配C x F 2 x +1 CHO的红外光谱。关于文献数据和CxF2x + 1CHO的大气命运讨论了结果。
The gas phase tropospheric removal of fluoroaldehydes (CxF2x+1CHO, x = 3, 4, 6)
作者:G. Solignac、A. Mellouki、G. Le Bras、Mu Yujing、H. Sidebottom
DOI:10.1039/b703741b
日期:——
The rate coefficient of the OH reaction with the perfluoroaldehydes C3F7CHO and C4F9CHO have been determined in the temperature range 252–373 K using the pulsed laser photolysis–laser induced fluorescence (PLP-LIF) method: kC3F7CHO+OH = (2.0 ± 0.6) × 10−12 exp[−(369 ± 90)/T] and kC4F9CHO+OH = (2.0 ± 0.5) × 10−12 exp[−(356 ± 70)/T] cm3 molecule−1 s−1, corresponding to (5.8 ± 0.6) × 10−13 and (6.1 ± 0.5) × 10−13 cm3 molecule−1 s−1, respectively, at 298 K. The UV absorption cross sections of these two aldehydes and CF3(CF2)5CH2CHO have been measured over the range 230–390 nm at 298 K and also at 328 K for CF3(CF2)5CH2CHO. The obtained results for C3F7CHO and C4F9CHO are in good agreement with two recent determinations but the maximum value of the absorption cross section for CF3(CF2)5CH2CHO is over a factor of two lower than the single one recently published. The photolysis rates of C3F7CHO, C4F9CHO and CF3(CF2)5CHO have been measured under sunlight conditions in the EUPHORE simulation chamber in Valencia (Spain) at the beginning of June. The photolysis rates were, respectively, Jobs = (1.3 ± 0.6) × 10−5, (1.9 ± 0.8) × 10−5 and (0.6 ± 0.3) × 10−5 s−1. From the Jobs measurements and calculated photolysis rate Jcalc, assuming a quantum yield of unity across the atmospheric range of absorption of the aldehydes, quantum yields Jobs/Jcalc = (0.023 ± 0.012), (0.029 ± 0.015) and (0.046 ± 0.028) were derived for the photodissociation of C3F7CHO, C4F9CHO and CF3(CF2)5CHO, respectively. The atmospheric implication of the data obtained in this work is discussed. The main conclusion is that the major atmospheric removal pathway for fluoroaldehydes will be photolysis, which under low NOx conditions, may be a source of fluorinated carboxylic acids in the troposphere.