CH2Cl Group Research Articles

ChemInform Abstract: REARRANGEMENT OF POLYCHLOROALKYL RADICALS WITH 1,4, 1,5, AND 1,6 MIGRATION OF HYDROGEN ATOM

1. During the reduction of 1,1,1,7-tetrachloroheptane with isopropanol in the presence of Fe(CO)5, together with the main reaction product 1,1,7-trichloroheptane (II), 1,1,5,7-tetrachloroheptane (III), 1,1,4,7-tetrachloroheptane (IV) and 7,7-dichloro-1-heptene (V) are formed in a total yield of 7% of theoretical. 2. The formation of (III), (IV), and (V) is explained by an unusual rearrangement of the CCl2(CH2)6Cl radicals into less stable radicals with 1,5-, 1,4-, and 1.6-migration of hydrogen atoms, respectively, with preferential formation of the rearrangement product and 1,5-migration of the hydrogen atom. 3. Certain regularities in the13C NMR spectra of polychlorohydrocarbons with a normal structure, containing the CHCl2, CH2Cl, and CHCl groups with different disposition of the CHCl group in the chain are discussed.

Rearrangement of polychloroalkyl radicals with 1,4-, 1,5- and 1,6-migration of hydrogen atom

1. During the reduction of 1,1,1,7-tetrachloroheptane with isopropanol in the presence of Fe(CO)5, together with the main reaction product 1,1,7-trichloroheptane (II), 1,1,5,7-tetrachloroheptane (III), 1,1,4,7-tetrachloroheptane (IV) and 7,7-dichloro-1-heptene (V) are formed in a total yield of 7% of theoretical. 2. The formation of (III), (IV), and (V) is explained by an unusual rearrangement of the CCl2(CH2)6Cl radicals into less stable radicals with 1,5-, 1,4-, and 1.6-migration of hydrogen atoms, respectively, with preferential formation of the rearrangement product and 1,5-migration of the hydrogen atom. 3. Certain regularities in the13C NMR spectra of polychlorohydrocarbons with a normal structure, containing the CHCl2, CH2Cl, and CHCl groups with different disposition of the CHCl group in the chain are discussed.

Structure of chlorinated poly(vinyl chloride). IV. Chlorination of β,β‐d2‐poly(vinyl chloride) as model for determination of the mechanism of chlorination

AbstractChlorinated β,β‐dideuterated poly(vinyl chloride) (β,β‐d2‐CPVC) was prepared by photochemical suspension chlorination in concentrated hydrochloric acid with chloroform as swelling agent, and thermally in tetrachloroethane solution. 1H‐NMR (nuclear magnetic resonance) spectra of β,β‐d2‐CPVC were recorded. The content of deuterium was determined in combustion products of β,β‐d2‐CPVC as the D2O:(H1D)2O ratio by means of mass spectroscopy. Both in the photochemical suspension chlorination and in the thermal solution chlorination of β,β‐d2‐PVC, a decrease of the concentration of CHCl groups was observed. The differences in structure of the suspension chlorinated and solution chlorinated β,β‐d2‐PVC were confirmed.

Branching in the PVC chain

Abstract The development of our belief that the branches in PVC are CH2 Cl groups and a further mechanism for their production are given. Published IR figures for these branches are likely to be 2.5 times too large.

A study of the molecular structure of monochloro-acetic acid by means of gas electron diffraction

The results of an interpretation of the gas electron diffraction pattern of monochloroacetic acid at 170 °C and a microwave investigation by Van Eijck et al. from this laboratory were combined. Three conformations with respect to internal rotation around the C—C bond were found, viz. 56% of a conformation with C 5 molecular symmetry and the C—Cl bond eclipsed with the C=O bond, 30% of a conformation with the CH 2Cl group rotated 131° from the former position and the remaining 14% of a conformation with 79° rotation of the CH 2Cl group. The bond lengths and the bond angles determined by means of this procedure are (standard deviations in parentheses): C—Cl: 1.778(0.005), C—C: 1.508 (0.006), C=0:1.223(0.004), C—0: 1.352(0.005), C—H: 1.09(0.02), O—H: 0.97 (0.015) Å; C—C=O: 126.1(0.5), C—C—O:110.6(0.4), C—C—C1:112.5(0.4), C—O—H: 105.8(1.1)°. A conformational distribution obtained by means of CNDO/2 calculations is not in agreement with our experimental radial distribution.

Carbon‐13 NMR spectra of some polychloro hydrocarbons and related compounds

AbstractData derived from the carbon‐13 NMR spectra of 37 organic polychloro compounds allow one to identify readily the CHCl2, CCl2 and CH2Cl groups, the 13C signals of which are registered in the shift ranges of 67 to 78 (80), 85 to 96 and 38 to 55 (59) ppm (from TMS), respectively, and have the distinctive one bond spin‐spin coupling constants 1J(CH) 170 to 184 Hz (for the CHCl2 groups) and 147 to 158 Hz (for the CH2Cl groups). The CCl2CH2CH2Cl fragment features characteristic diamagnetic shieldings of the CCl2 and CH2Cl that may be related to increased electron density on both of these groups.

Carbon‐13 NMR spectra of some polychlorinated telomerisation products

AbstractThe study of 28 specially selected compounds containing chlorine shows that 13C NMR signals of the CCl3, CCl3CH2 and CH2Cl groups are registered in the ranges of 93 to 105, 49 to 71 and 38 to 59 ppm (from TMS), respectively and are readily identified in 13C NMR spectra of polychloro compounds. The weak electron withdrawing ability of the CCl3CHCl and CH2Cl groups, as well as the extremely strong influence of CCl3 and CH2Cl groups on the methylene group between them in 1,1,1,3‐tetrachloropropane, is noted.

ChemInform Abstract: ORGANOSILICON COMPOUNDS PART 110, (29)SI‐NMR CHEMICAL SHIFTS IN ORGANOSILICON COMPOUNDS (I), SUBSTITUENT EFFECT OF CH2CL GROUP

Chemischer InformationsdienstVolume 5, Issue 27 Organoelement Compounds ChemInform Abstract: ORGANOSILICON COMPOUNDS PART 110, (29)SI-NMR CHEMICAL SHIFTS IN ORGANOSILICON COMPOUNDS (I), SUBSTITUENT EFFECT OF CH2CL GROUP E. LIPPMAA, E. LIPPMAASearch for more papers by this authorM. MAEGI, M. MAEGISearch for more papers by this authorG. ENGELHARDT, G. ENGELHARDTSearch for more papers by this authorH. JANCKE, H. JANCKESearch for more papers by this authorV. CHVALOVSKY, V. CHVALOVSKYSearch for more papers by this authorJ. SCHRAML, J. SCHRAMLSearch for more papers by this author E. LIPPMAA, E. LIPPMAASearch for more papers by this authorM. MAEGI, M. MAEGISearch for more papers by this authorG. ENGELHARDT, G. ENGELHARDTSearch for more papers by this authorH. JANCKE, H. JANCKESearch for more papers by this authorV. CHVALOVSKY, V. CHVALOVSKYSearch for more papers by this authorJ. SCHRAML, J. SCHRAMLSearch for more papers by this author First published: July 9, 1974 https://doi.org/10.1002/chin.197427296AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume5, Issue27July 9, 1974 RelatedInformation

The conformations of RS and RR-1,2,5,6-tetrachloro- hexane and SrSr-2,3,6,7-tetrachlorooctane in the liquid and crystalline phases studied by infrared

The results of a combined infrared and nuclear magnetic resonance study of the meso (RS) and dl (RR) stereoisomers of 1,2,5,6-tetrachlorohexane and one meso (SRSR) form of 2,3,6,7-tetrachlorooctane are discussed with respect to the conformations of these molecules in solution, liquid and crystalline states. The predominant rotational isomer in the liquid in each case has an extended zig-zag conformation of the carbon skeletal chain; the vicinal chlorine atoms are mainly trans to each other, although other isomers occur with gauche vicinal chlorine atoms. In the crystalline phase only the extended form with trans vicinal chlorine atoms is found, except for meso-tetrachlorohexane where internal rotation of the CH 2Cl groups leads to an extended conformation with gauche vicinal chlorine atoms. On the basis of the present results, it seems most likely that extended conformations will also be preferred in the other three stereoisomers of 2,3,6,7-tetrachlorooctane.

ChemInform Abstract: ORGANOSILICON COMPOUNDS PART 109, SILICON‐29 NMR CHEMICAL SHIFTS IN ORGANOSILICON COMPOUNDS CONTAINING CH2CL GROUP

Chemischer InformationsdienstVolume 5, Issue 15 Organoelement Compounds ChemInform Abstract: ORGANOSILICON COMPOUNDS PART 109, SILICON-29 NMR CHEMICAL SHIFTS IN ORGANOSILICON COMPOUNDS CONTAINING CH2CL GROUP J. SCHRAML, J. SCHRAMLSearch for more papers by this authorJ. VCELAK, J. VCELAKSearch for more papers by this authorV. CHVALOVSKY, V. CHVALOVSKYSearch for more papers by this author J. SCHRAML, J. SCHRAMLSearch for more papers by this authorJ. VCELAK, J. VCELAKSearch for more papers by this authorV. CHVALOVSKY, V. CHVALOVSKYSearch for more papers by this author First published: April 16, 1974 https://doi.org/10.1002/chin.197415305Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume5, Issue15April 16, 1974 RelatedInformation

Silicon-29 NMR chemical shifts in organosilicon compounds containing CH2Cl group

Silicon-29 NMR chemical shifts in organosilicon compounds containing CH2Cl group

29Si-NMR chemical shifts in organosilicon compounds. Substituent effect of CH2Cl group

29Si-NMR chemical shifts in organosilicon compounds. Substituent effect of CH2Cl group

Conformational analysis of certain compounds containing the P(O)CH2Cl group

1. The three-dimensional structure of certain compounds containing a P(O)CH2Cl group was considered on the basis of an analysis of the data of the IR spectra, dipole moments, and Kerr constants. All the compounds studied in solutions are characterized by an equilibrium of the gauche- and trans-conformera, the position of which depends on the nature of the substituents at the phosphorus atom. 2. The factors determining the energetic stability of the conformers were evaluated quantitatively. In the absence of voluminous substituents, the determining role is played by electrostatic interactions. 3. The frequency of the valence vibrations of the phosphoryl group depends on the steric orientation of the irregular group.

Force constants and normal vibrations of the haloacetonitriles

Normal coordinate calculations were carried out for fluoro-, chloro-, bromo- and iodoacetonitrile, using a seventeen-parameter valence force field. Most of the force constants have different values in the four halides that change in a regular manner. The a″ vibrations are essentially pure, but there is considerable mixing of normal modes in the a′ species. The difference in previous vibrational assignments is resolved but the bands assigned to the C-C-Br and C-C-I bends were found to be mainly C-Br and C-I stretching vibrations. Transferability of the force constants obtained for the CH2Cl group seems quite good.

Determination of chlorine distribution in chlorosulfonated polyethylenes by high‐resolution NMR spectroscopy

AbstractHigh‐resolution proton magnetic resonance (NMR) spectroscopy was used to determine the sequence distribution of chlorines in elastomeric chlorosulfonated polyethylenes. The determination is based on measuring the relative amounts of methylene groups that are α, β, and γ (or greater) from chlorine containing groups (CHCl groups) in chlorosulfonated polyethylenes. The results obtained from the NMR examination at 220 MHz were compared with the theoretical predictions based on the statistics of substitution polymers. The comparison showed that polyethylenes chlorosulfonated by a solution reaction with gaseous chlorine and sulfur dioxide show a random chlorine distribution.

Action of magnesium on polyhaloalkanes and polyhaloalkenes and synthesis of 5, 5-dichloropentaneboronic acid

1. The bromides CHCl2(CH2)nCH2Br and CCl2=CH(CH2)nBr, where n=3 and 5, react with magnesium in ether to give ω,ω-dichloroalkyl (alkenyl)magnesium bromides, in yields of 40–50% for n=3, and 10–20% for n=5. The condensation products [CHCl2(CH2)nCH2-]2 and [CCl2=CH(CH2)n-]2 are also formed in 10–30% of the theoretical yields. 2. 5, 5-Dichloropentaneboronic acid, identified as the iminodiethyl ester, was synthesized from the Grignard reagent, obtained from 1, 1-dichloro-5-bromopentane and magnesium. 3. Bromides of the type CHCl2(CH2)nCH2Br and CC12=CH(CH2)nBr, where n=3 and 5, were obtained from the corresponding chlorides by exchange of the chlorine in the CH2Cl group by bromine.

Force constants for 3-chloropropyne and chloro-2-butyne

Normal coordinate calculations were carried out for H-C=C-CH2Cl using a valence force field and the force constants obtained were transferred to CH3-C=C-CH2Cl. There seem to be small but significant differences in some of the force constants of the -CH2Cl group of these two molecules. The vibrational assignment of McLachland [1] is confirmed, and the calculations show that the fundamental vibrations are relatively pure except for the C-C symmetric stretch and the skeletal bends.

A study of the transfer of the electronic influence of substituents in o-carboranes by nuclear quadrupole resonance

The 35Cl NQR spectra of 2-substituted 1-chloromethyl-o-carboranes and of 1-chloromethyl-9,12-dihalogeno-o-carboranes have been investigated. The anomalous influence of two halogen atoms present in positions 9 and 12 of the carborane nucleus on the electron density of the chlorine atom in the CH2Cl group is explained by the combined action of their −I and +M effects, and also by the effect of p → d conjugation. The comparatively high 35Cl NQR frequency for o-ClCH2CB10H10CH is due to the large −I effect of the carboranyl group. The induction constants of a number of groups attached to the carborane ring have been evaluated. In the molecules of the 2-substituted 1-chloromethyl-o-carboranes spatial interaction between X and Cl clearly appears. The substituents X in compounds of this series can be divided into three types according to their electronic influence: 1) electron-donating substituents, 2) substituents containing a mobile hydrogen atom (capable of forming a hydrogen bond), and 3) substituents possessing an unshared pair of electrons capable of passing into the vacant 3d orbital of a chlorine atom.

Vibrational analysis of a series of n-alkyl chlorides in the solid state: Ethyl chloride through n-hexyl chloride

The infrared spectra of a series of n-alkyl chlorides, ethyl through n-hexyl, have been measured in the solid state at low temperature. Only two conformations of each molecule (for ethyl chloride only one) were found to be present. In both forms the carbons are coplanar. In one case (trans) the chloride is also in the plane and in the other (gauche) it is not. A nearly complete vibrational assignment for each form is given for the region 1500-290 cm −1. The analysis is based on normal coordinate calculations using force constants most of which were transferred from the n-paraffins. Twelve of the constants associated with the -CH 2Cl group were adjusted until the average error between the calculated and observed frequencies of some 210 fundamentals reduced to 3.9 cm −1. These results support our recent interpretation of the vibrations of the extended n-paraffins.

Spectroscopic and acoustic studies in relation to the structure of some 1,3-dioxolan-2-ones

N.m.r., i.r., and ultrasonic absorption measurements on the heterocyclic molecule 1,3-dioxolan-2-one and its 4-methyl and 4-chloromethyl derivatives have shown that the ring structures are very similar in these compounds. In the chloromethyl derivative two of three possible rotational isomers formed by internal rotation of the –CH2Cl group were identified from their i.r. spectra and the ultrasonic data were consistent with this conclusion. The experimental data, however, do not preclude the existence of the third rotational isomer.