(Vapor + liquid) phase equilibrium measurements for {trifluoroiodomethane (R13I1) + propane (R290)} from T = (258.150 to 283.150) K

In this paper, the (vapor + liquid) equilibrium data for (R13I1 + R290) were measured by a vapor-recirculation apparatus at temperatures from (258.150 to 283.150) K. The VLE data were correlated by the Peng–Robinson equation of state with two different models, the van der Waals mixing rule, and the Huron–Vidal mixing rule involving the NRTL activity coefficient model. Good agreements were found between the calculated data and the experimental data. The maximum average absolute relative deviation of pressure (AARD p) was 0.48%, while the maximum average absolute deviation of composition (AAD y) was 0.0040. Meanwhile, zeotropic behavior can be found for the measured system in this study. The total combined standard uncertainties for temperature, pressure and composition measurements were ±5 mK, ±0.0005 MPa and ±0.005, respectively.     

KNO_3/AC负载型固体碱气相催化合成CF_3I的性能

考察了KNO3/AC负载型固体碱催化剂对五氟乙烷和碘气相碘化合成CF3I反应的催化性能.通过扫描电镜(SEM)、N2物理吸附、热分析-质谱联用(DSC/TG-MS)、傅里叶红外光谱(FT-IR)、X射线衍射(XRD)等手段研究了改性前后活性炭载体的表面性质和KNO3在载体表面的分解行为.结果表明,KNO3负载到活性炭载体,其分解温度从527℃降至250℃,DSC/TG-MS、FT-IR表征确定了KNO3在活性炭载体上的分解区间为250℃～400℃,源于活性组份与载体的强相互作用.XRD表征显示随着焙烧温度的提高,KNO3逐渐分解成KOx碱性物种.催化剂评价结果显示,在常压下反应温度为500℃,空速100 h-1,n(C2F5H)/n(I2)=1的条件下,C2F5H的转化率为49.7%,CF3I的选择性为70.5%.     

Sodium dithionite initiated addition of CF2Br2, CF3I and (CF3)2CFI to allylaromatics: Synthesis and the reactivity of 4-aryl-1,1-difluorodienes and 4-aryl-1,1-bis(trifluoromethyl)dienes

Sodium dithionite initiated addition of CF₂Br₂, CF₃I and (CF₃)₂CFI to the terminal double bond of allylbenzenes and of (CF₃)₂CFI to allylpyridines in a MeCN/H₂O system were investigated. The reactions of CF₂Br₂ with allylbenzenes gave comparable amounts of adducts, 1-(2,4-dibromo-4,4-difluorobutyl)benzenes, debrominated products,1-(4-bromo-4,4-difluorobutyl)benzenes, and dimeric compounds in total yields 40-66%. Treatment of the adducts with DBU resulted in double dehydrohalogenation affording 4-aryl-1,1-difluorobutadienes which undergo Diels-Alder condensation with nitrogen dienophiles to give N-heterocycles with difluoromethylene group in the ring. The reactions of CF₃I and (CF₃)₂CFI with allylbenzenes gave the respective adducts, (4,4,4-trifluoro-2-iodobutyl)benzenes and 1-(4,5,5,5-tetrafluoro-4-(trifluoromethyl)-2-iodopentyl)benzenes as the main products. Dehydrohalogenation of these adducts resulted, respectively, in (4,4,4-trifluoro-but-1-enyl)benzenes and 4-aryl-1,1-bis(trifluoromethyl)butadienes in high yields. (CF₃)₂CFI reacted rapidly with allylpyridines to give mixtures from which, after treatment with DBU, 4-pyridyl-1,1-bis(trifluoromethyl)butadienes were isolated in a ca. 60% yield.