35 NQR Spectra of Substituted N-(phenyl)-2-chloroacetamides

Svoboda

2000

Self Cite

The effect of side chain and ring substitutions on the crystal structures of N-(2,4,6-substitutedphenyO-chloroacetamides of the type, 2,4,6-X 3 C 6 H 2 -NHCO-CH 3 _ v Cl y (X = CH 3 or Cl and 1 < y < 3), has been studied by determining the crystal structures of N-(2,4,6-trimethylphenyl)-2-chloroacetamide, 2,4,6-(CH 3 ) 3 C 6 H 2 -NHCO-CH 2 Cl (TMPMCA); N-(2,4,6-trichlorophenyl)-2-chloroacetamide, 2,4,6-Cl 3 C 6 H 2 -NHCO-CH 2 Cl (TCPMCA); N-(2,4,6-trichlorophenyl)-2,2-dichloroacetamide, 2,4,6-Cl 3 C 6 H 2 -NHCO-CHCl 2 (TCPDCA) and N-(2,4,6-trichlorophenyl)-2,2,2-trichloroacetamide, 2,4,6-Cl 3 C 6 H 2 -NHCO-CCl 3 (TCPTCA). The crystal type, space group, formula units and lattice constants in A are: (TMiPMCA); monoclinic, P2,/n, Z = 8, a = 9.029 (5)

Section: Preparation and Characterisation Of The Compoundsunclassified

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Structural Studies of N-(2,4,6-trisubstitutedphenyl)-Chloroacetamides, 2,4,6-X₃C₆ H₂ -NHCO-CH_{3_y}Cl_y, (X = CH₃ or Cl and y = 1 -3)

Svoboda

2000

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“…Amides are of fundamental chemical interest, as conjugation between the nitrogen lone pair electrons and the carbonyl 7r-bond results in distinct physical and chemical properties [4], The amide moiety is an important constituent of many biologically significant compounds [4,5]. We are thus interested in structural studies of amides in their crystalline state using this combined tool [6][7][8][9][10][11][12][13][14][15].…”

Section: Introductionmentioning

confidence: 99%

³⁵CI NQR and Structural Studies of N-(2,6-Dichlorophenyl)-Amides, 2,6-Cl₂C₆H₃-NHCO-R (R = H or CH_3-yX_y and X = CH₃ or CI; y = 0,1, 2 or 3)

Paulus

2000

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The effect of side chain substitution on the 35CI NQR and crystal structure of amides of the type N-(2,6-dichlorophenyl)-amides, 2,6-Cl2C6H3-NHCO-R (R = H or CH3_yXy where X = CH3 or CI and y = 0, 1, 2 or 3), has been studied by measuring the 35C1 NQR spectra and determining the crystal structures of the compounds N-(2,6-dichlorophenyl)-formamide, 2,6-Cl2C6H3- NHCO-H (DCPFA); N-(2,6-dichlorophenyl)-2-methylacetamide(propionamide), 2,6-Cl2C6H3- NHCO-CH2CH3 (DCPMA); N-(2,6-dichlorophenyl)-2,2-dimethylacetamide(isobutyramide), 2,6- Cl2C6H3-NHCO-CH(CH3 ) 2 (DCPDMA) and N-(2,6-dichlorophenyl)-2,2,2-trimethylacetamide (neopentylamide), 2,6-Cl2C6H3-NHCO-C(CH3)3 (DCPTMA), and by analysing the present data along with the 35CI NQR spectra and / or crystal structures of the compounds, 2,6-dichloroaniline, 2,6-Cl2C6H3-NH2 (DCA), N-(2,6-dichlorophenyl)-acetamide, 2,6-Cl2C6H3--NHCO-CH3 (DCPA), N-(2,6-dichlorophenyl)-2-chloroacetamide, 2,6-Cl2C6H3-NHCO-CH2Cl (DCPCA), N- (2,6-dichlorophenyl)-2,2-dichloroacetamide, 2,6-Cl2C6H3-NHCO-CHCl2 (DCPDCA) and N- (2,6-dichlorophenyl)-2,2,2-trichloroacetamide, 2,6-Cl2C6H3-NHCO-CCl3 (DCPTCA). The crystal type, space group, formula units and lattice constants in A of the new structures are;DCPFA: orthorhombic, Pbca, Z = 8, a = 8.593(3), b = 12.728(4), c = 14.376(4); DCPMA: orthorhombic, P212121, Z = 4, a = 4.774(2), b = 10.961(5), c = 19.562(8); DCPDMA: monoclinic, P21/c, Z = 4, a = 9.901(4), b = 13.785(5), c = 9.060(3), ß = 103.58(2)° and DCPTMA: monoclinic, P21/n, Z = 8, a = 16.047(5), b = 9.882(3), c = 16.270(5) ß = 102.12(1)°. The compound, DCPTMA shows two molecules in its asymmetric unit. This is in agreement with the multiple lines observed in the 35CI NQR spectra of the compound. The conversion of DCA (monoclinic) into it's various acid amides DCPFA, DCPA, DCPMA, DCPDMA, DCPTMA, DCPCA and DCPTCA affects it's crystal symmetry. The replacement of the side chain CH3 in DCPA by the H atom or substitution of either a CH3 group or a CI atom for one of the H atoms in the side chain CH3 or replacement of the two ring CI atoms by the H atoms changes it's crystal symmetry from monoclinic to orthorhombic, while the substitution of 2 or all the 3 H atoms in the CH3 group of DCPA by 2 or 3 CH3 groups or CI atoms restores it's crystal symmetry back to the monoclinic type. The bond lengths and bond angles are normal except for some deviations.

“…But there are no reports on the effects of electron donating or repelling group substitutions in the phenyl ring on the 35 CI NQR Cl(c<;) frequencies of the dichloroacetyl group, as chlorine is electron withdrawing. We have recently reported the effects of electron donating or repelling group substitutions in the phenyl ring on the 35 CI NQR Cl(u;) frequencies of the 2-chloroacetyl [16] and 2,2,2-trichloroacetyl groups in the arylamides [ 15]. To complete our work aimed at correlating 35 CI NQR frequencies of the substituted N-phenylchloroacetamides represented by the general formula X y C 6 H 5 _ y NHCOR (where X = CI or CH 3 , y = 1 or 2 and R = CH 2 C1, CHC1 2 or CC1 3 ) with their chemical bond parameters, we have studied 35 C1 NQR spectra of several N-(methylsubstitued phenyl)-2,2-dichloroacetamides and hence intercorrelated the frequencies of all the substituted N-phenyl-2-chloro, 2,2-dichloro and 2,2,2-trichloro-acetamides and with their chemical bond parameters.…”

mentioning

confidence: 99%

Cl NQR Spectra of N-(substitutedphenyl)-2,2-dichloroacetamides and Correlation of ³⁵ Cl NQR γCl(ω) of Substituted N-Phenyl- Chloroacetamides X_yC₆H_5-yNHCOR (X = Cl or CH₃ , y = 1 or 2, R = CH₂Cl, CHCl₂ or CCl₃)

Kumar

2000