Trans- 1,2-dichloroethane

Table 11.2 AGep values (kcal moD ) for trans 1.2-dichloroethane as a function of the truncation point in the multipole moment expansion"...

We are going to apply the SQM method to the existing Hessian matrix for trans-1,2-dichloroethane in order to improve the agreement with experiment furthermore, we will also need to consider the gauche conformer which will almost certainly contribute to the experimental vibrational spectra at room temperature. 

Predicted SQM Raman spectra for 1,2-dichloroethane (a) Raman spectrum for trans-1,2-dichloroethane, (b) Raman spectrum for gouchc-1,2-dichloroethane, (c) Raman spectrum for 1,2-dichloroethane at room temperature... 

Finally O Table 10-8 compares optimized geometrical parameters for trans-1,2-dichloroethane with experimental electron diffraction data from Kvesethi as reported in El Youssoufi et al. (1998a, b). 

Rey et al. ° removed chlorinated aromatic hydrocarbon from a pharmaceutical plant by stripping the chlorinated hydrocarbons with air and then adsorbing in activated carbon beds. The removal of chlorinated volatile organic compounds such as trichloroethane, cis, and trans dichloroethane from ground water contaminated with these nonaqueous liquids was carried out by Yu et al." using activated carbon fibers. All the halogenated compounds were adsorbed rapidly by the activated carbon... 

We ran an SCRF single point energy calculation for gauche dichloroethane conformers in cyclohexane (e=2.0), using the Onsager model at the Hartree-Fock and MP2 levels of theory (flfl=3.65) and using the IPCM model at the B3LYP level. The 6-31+G(d) basis set was used for all jobs. We also ran gas phase calculations for both conformations at the same model chemistries, and an IPCM calculation for the trans conformation (SCRF=Dipole calculations are not necessary for the trans conformation since it has no dipole moment). 

Remember that the trans form of dichloroethane has no dipole moment, so it is not necessary to compute its energy in solution with the Onsager model. 

Dichloroethane acts as a mild chlorinating agent towards trans-Me3SiPtCl(PEt3)2 [Eq. (73) (114)], and CDCI3 caused the conversion of Ph3SiZr(Cl)Cp2 into CpjZrC (166). 

In 1964, Kochetkov, Khorlin and Bochkov reported that the reaction of 1,2-alky-lorthoacetates with alcohols in the presence of catalytic amounts of HgBr2 and pTsOH furnished acetylated 1,2-trans glycosides or isomeric orthoesters depending on the reaction conditions [4]. Polar solvents (nitromethane, acetonitrile) and large amounts of catalyst promoted glycosylation (a, Scheme 5.5), whereas solvents of low polarity (dichloroethane) and the use of small amounts of catalyst favored transorthoesterification (b, Scheme 5.5) [16]. 

Now, consider what happens if the two fluorines are replaced by two chlorines. In this case, the dominant interactions will be acci-° ci because the C—Cl bond is both a better donor and a better acceptor than the C-H bond. Hence, it is predicted that 1,2-dichloroethane will have a preferred trans conformation which combines in an anti orientation the best donor and best acceptor bonds. 

Chloroacetic acid, see Allidochlor. Allyl chloride, 1,1-Dichloroethane, cfs-l,3-Dichloropropylene, trans-... 

Dichloroethane, 1,1-Dichloroethylene, trans-, 2-Dichloroethylene, Tetrachloroethylene, 1,1,1-Trichloroethane, 1,1,2-Trichloroethane, Trichloroethylene Vinyl phosphates, see Mevinphos Vinyltoluene, see Styrene... 

Steyaert, G., Lisa, G., Gaillard, P., et al. (1997) Intermolecular forces expressed in 1,2-dichloroethane-water partition coefficients. J. Chem. Soc. Faraday Trans. 93, 401-406. 

Boc-(R,/ )-/ra s-ACHC-OBzl (31 0.047 g, 0.14 mmol) was dissolved in 4M HCl/dioxane (0.5 mL) and stirred for 1 h. The solvent was then removed under a stream of N2, and the residue 34 was dried under vacuum. Boc-(f ,f )-trans-ACHC-OH (33 0.034g, 0.14mmol) and DMAP (0.023g, 0.19mmol) were added followed by DMF (lmL). EDC (0.059 g, 0.31 mmol) was added, and the reaction was stirred for 48 h under N2. Solvent was removed under a stream of N2, and the residue was further dried under vacuum. To this residue was added 1M HQ ( 3mL) and the solid that did not dissolve was isolated by suction filtration and washed with additional 1M HC1. The solid was dried under vacuum yield 0.051 g (79%). Fluffy crystals were grown by vapor diffusion of heptane into a soln of 35 in 1,2-dichloroethane mp 195 °C. 

The authors prefered the latter explanation. They argue that the difference in the dielectric constant of the medium, when a hydrocarbon rich mixture is compared with that rich in sulfur dioxide, affects the ratio of gauche to trans conformations of the polymer chain. Such effects were observed in other systems, e.g. in 1,2 dichloroethane (38). Hence,... 

Christie and Breckenridge (42) describe the application of this column to the isolation and determination of FAs containing trans double bonds in samples of natural and industrial origin. A column (250 X 4.6-mm ID) of NUCLEOSIL 5SA was flushed with 1% ammonium nitrate solution at a flow rate of 0.5 ml/min for 1 h, then with distilled water at 1 ml/min for 1 h. Silver nitrate (0.2 g) in water (1 ml) was injected onto column via the Rheodyne valve in 50-yu.l aliquots at 1-min intervals silver began to elute from the column after about 10 min, and 20 min after the last injection the column was washed with methanol for 1 h, then with 1,2-dichloroethane-dichloromethane (1 1 v/v) for 1 h. For most of the analytical work, the column temperature was maintained at 30°C in a thermostatted oven. 1,2-Dichloroethane-dichloromethane (1 1) (mixture A) at a flow rate of 1.5 ml/min was the mobile phase (detector operated at 242 nm) for the separation of isomeric monoenes, and the same solvents with the addition of 0.5% acetonitrile (mixture B) at a flow rate of 0.75 ml/min were employed for isomeric dienes and trienes. 

Furthermore, in the addition of bromine to 44 (in 1,2-dichloroethane, chloroform or carbon tetrachloride, see Scheme 19) to obtain the trans dibromo derivative99 (47), which is found to be in two main conformers100, the formation of the bromonium ion (46) from 5//-dibenz[ >,/]azepine-5-carbonyl chloride (44) is a reversible step. The formation of the bromonium ion (46) follows the association of reagents in the CT complex (45). 49 reacts with hydrogen bromide through the protonated 48, forming" both the dibromo derivative 47 and the olefin 44. The bromonium ion (46) is the probable intermediate... 

---