Research Progress on Dehalogenation Reaction

Synthesis and Herbicidal Activities of 2-Ethoxyethyl 2-Cyano-3-(substituted)acrylates

“…Anal. calcd for C 15 H 17 FN 2 O 3 S: C 55.54, H 5.28, N 8.64; found C 55.37, H 5.10, N 8. 17.3,64.3,66.8,67.9,77.4,116.2 (d,J＝22.8 Hz) 4,64.4,66.7,67.8,78.6,104.6 (dd,J＝2.9,23.4 Hz),111.6 (dd,J＝18.4,3.8 Hz),116.7,121.8 (dd,J＝8.1,4.1 Hz),128.6 (d,J＝ 10.0 Hz),155.7 (dd,J＝239.0,12.1 Hz),160.5 (dd,J＝ 239.3,10.8 Hz) 1,17.5,64.6,66.9,67.9,78.5,117.1(d,J＝22.4 Hz),119.4,122.0,125.0 (d,J＝7.3 Hz),127.4,134.2,156.0 (d,J＝246.3 Hz), 167.5, 170.5; MS (EI, 70 eV) m/z (%): 358 (M ＋ , 27), 311 (20), 268 (71), 239 (15), 221 (100), 193 (14), 168 9 11 mL (162 mmol)氨水和 10 mL 丙酮的混合液中, 室温 搅拌 12 h, 旋转蒸发除去溶剂后加入 50 mL 水, 摇匀, 抽滤, 烘干滤饼并用乙醇重结晶 [12,13] .…”

Regioselective alkali metal reduction of dibenzocyclooctadiene lignan derivatives, demethoxylation followed by dehalogenation

“…Aryl halides are very useful in organic syntheses, such as acting as substrates in transition-metal-catalysed coupling reactions and for the preparation of Grignard reagents. However, their toxicities are the focus in environmental protection measures [ 2 ]. Thus far, four different aryl-halide dehalogenation methods involving transition-metal catalysts [ 2 – 17 ], photochemistry [ 18 – 21 ], free-radical reductions [ 22 ], and two-electron transfer by super-electron donors have been investigated [ 22 ].…”

“…However, their toxicities are the focus in environmental protection measures [ 2 ]. Thus far, four different aryl-halide dehalogenation methods involving transition-metal catalysts [ 2 – 17 ], photochemistry [ 18 – 21 ], free-radical reductions [ 22 ], and two-electron transfer by super-electron donors have been investigated [ 22 ]. Although high yields can be achieved using these methods [ 10 – 23 ], several factors must be considered, including the high cost of expensive metal catalysts, the inaccessibility of organic super-electron donors, strict reaction conditions that always involve high temperatures, long reaction time, and complicated combinations of reagents.…”