Structural determination of monosubstituted alkylbenzenes by proton magnetic resonance

Yamamoto, Osamu; Hayamizu, Kikuko; Sekine, Kiyoharu.; Funahira, Shuji.

doi:10.1021/ac60319a010

Cited by 15 publications

(4 citation statements)

References 26 publications

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“…1 H NMR (CCl 4 ) d 7.17 (m 4H), 3.39 (apparent q, J 7.0 Hz, 2H), 2.74 (t, J 7.5 Hz, 2H), 1.85 (s, 3H), 1.79 (m, 2H); 1 H NMR (CDCl 3 ) d 7.23 (m, 4H), 5.58 (b, 1H), 3.29 (apparent q, J 7.0 Hz, 2H), 2.76 (t, J 7.5 Hz, 2H), 1.96 (s, 3H), 1.83 (m, 2H); 13 C NMR (CDCl 3 ) d 170.1, 138.9, 133.7, 130.4, 129.5, 127.5, 126.9, 39.1, 30.9, 29.5, 23.3; MS m/z (%) 213 (M + • , 18), 211 (M + • , 59), 176 (19), 152 (29), 125 (34), 117 (53), 103 (25), 89 (17)…”

Section: N-(3-(2-chlorophenyl)propyl)acetamide (13b) Colourless Oil;mentioning

confidence: 99%

Aromatic chlorination of ω-phenylalkylamines and ω-phenylalkylamides in carbon tetrachloride and α,α,α-trifluorotoluene

et al. 2006

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The aromatic halogenation of simple alkylbenzenes with chlorine proceeds smoothly in acetic acid but is much less efficient in less polar solvents. By contrast chlorination of omega-phenylalkylamines, such as 3-phenylpropylamine, occurs readily in either acetic acid, carbon tetrachloride or alpha,alpha,alpha-trifluorotoluene, and in the latter solvents gives high proportions of ortho-chlorinated products. These effects are attributable to the involvement of N-chloroamines as reaction intermediates, with intramolecular delivery of the chlorine electrophile. Omega-phenylalkylamides, such as 3-phenylpropionamide, also easily undergo aromatic chlorination in carbon tetrachloride and alpha,alpha,alpha-trifluorotoluene. These reactions generally show a first-order dependence on the substrate concentration, but not on the amount of chlorine. With carbon tetrachloride, very similar reaction rates are observed with chlorine concentrations ranging from 0.1-1.5 M. In alpha,alpha,alpha-trifluorotoluene, the rates reach a plateau at a chlorine concentration of approximately 0.2 M. These features indicate that the reactions proceed via the formation of intermediates which evidence suggests may be the corresponding O-chloroimidates. Irrespective of the mechanistic details, the reactions are remarkably rapid, being faster than analogous reactions in acetic acid and three to four orders of magnitude more rapid than reactions of simple alkylbenzenes in carbon tetrachloride. Therefore, chlorination of the amines and amides may be accomplished without the need for highly polar solvents, added catalysts or large excesses of chlorine, which are often employed for electrophilic aromatic substitutions. Although the use of carbon tetrachloride is becoming increasingly impractical due to environmental concerns, the trifluorotoluene is a suitable alternative.

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Section: N-(3-(2-chlorophenyl)propyl)acetamide (13b) Colourless Oil;mentioning

confidence: 99%

Aromatic chlorination of ω-phenylalkylamines and ω-phenylalkylamides in carbon tetrachloride and α,α,α-trifluorotoluene

et al. 2006

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“…The concentrations (%, w/w) of compound, CS2, acetone-d6, DMSO-d6 and DCC1, are given, in that order, in parentheses. The TMS concentration was 1% in all cases: 2 (30,0,0, 69, 0); 3 (36, 0, 0, 0, 63); 4 (13, 65, 21, 0, 0); 5;21 6 (13, 65, 21, 0, 0); 7 (19, 61, 0, 19, 0); 8 (11, 66, 22, 0, 0); 9 (7, 70, 22, 0, 0); 10 (12, 0, 0, 0, 87); 11 (5, 0, 0, 0, 94); 12 (7,70,22,0,0); 13 (12, 66, 21, 0, 0); 14 (19,0,0,80,0); 15 (21, 59, 19, 0, 0); 16 (19,60,20,0,0); 17 (19, 0, 0, 0, 80); 18 (3,72,24,0,0); 19 (11, 66, 22, 0, 0); 20 (8,69,22,0,0); 21 (17, 0, 0, 82, 0); 22 (14, 61, 24, 0, 0); 23 (3, 47, 49, 0, 0); 24;l 25;' 26 (4, 0, 0, 0, 95).…”

Section: Experimental Spectramentioning

confidence: 99%

¹³C, ¹³C coupling constants and ¹³C chemical shifts of aromatic carbonyl compounds. Effects of ortho‐ and peri‐interactions involving the carbonyl substituent

1977

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Carbon-13 n.m.r. data have been determined for a series of 26 aromatic carbony4 compounds inciuding benzoyl, naphthoyl and pyrenoyl derivatives 13C labelled in the carbonyl group. Doubly labelled anthraquinone has also been included. The compounds investigated comprise non-hindered molecules and molecules in which the carbony1 substituent is subject to orthoor periinteractions affecting conjugation of the carbonyl group with the aromatic ring. The dependence of long range 13C,13t couplimg constants involving the carbonyl carbon, in particular ' J and "J, on steric conditions is discussed, as is the possibility of deciding on the orientation of the carbonyl bond. The following results have emerged. zJ(s-t)>zJ(s-c) for ketones and aldehydes, and the reverse is valid for acids and acid derivatives. (s-t and s-c refer to the orientation of the -0 group relative to the aromatic bond in question with respect to the connecting single bond). For ketones "J(t,~-c)<~J(f,s-t), and both of these "J(t) values decrease with increasing angle of twist, 8, about the single bond, whereas 3J(c,s-c) increases with 8. For acids and acid derivatives no shnilar regularity was found.(The initial f and c refer to the geometry of the three-bond coupling path). Generally it is found that "J( t ) > 3J(c) and 'J( r) > 'J, confirming earlier results. Theoretical calculations on a few model compounds are qualitatively in accordance With the experimental results. Some sign determinations for coupling constants are presented. A short discussion is given of substituent effects on chemical shifts. Observed trends are consistent with earlier results. nation of dipole moment^,^'^ 13C n.m.r. chemical shifts5-' and molar Kerr constants' have been applied. Also X-ray methods have been used." In the present work two-and three-bond coupling constants "J(C0,Ci) are discussed in connection with this problem. The observed coupling constants have also been compared with theoretical values corresponding to

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“…All reduction products described in this manuscript are known compounds, and for purposes of comparative identification, all but three were purchased commercially from Aldrich Chemical Co. Identification of the three noncommercial reduction products, 3-nitro-ethylbenzene, ethylphenyl sulfone, and O -propylglycidol, arising from reduction of 30 , 31 , and 33 , respectively, was made by comparison with literature data obtained from references indicated for each compound. Palladium-on-carbon and platinum oxide were purchased from Lancaster Synthesis and Aldrich Chemical Co., respectively.…”

Section: Methodsmentioning

confidence: 99%

An Immobilized Homogeneous Catalyst for Efficient and Selective Hydrogenation of Functionalized Aldehydes, Alkenes, and Alkynes

Burk¹,

Gerlach²,

Semmeril³

2000

J. Org. Chem.

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An immobilized cationic rhodium(I) catalyst bearing the diphosphine 1,1'-bis(diisopropylphosphino)ferrocene (DiPFc, 1) allows efficient and chemoselective hydrogenation of a range of functionalized aldehydes, as well as alkenes and alkynes, under mild conditions. This heterogenized catalyst system is convenient to prepare, is stable to air and moisture over extended periods, and is readily recycled.

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Structural determination of monosubstituted alkylbenzenes by proton magnetic resonance

Cited by 15 publications

References 26 publications

Aromatic chlorination of ω-phenylalkylamines and ω-phenylalkylamides in carbon tetrachloride and α,α,α-trifluorotoluene

Aromatic chlorination of ω-phenylalkylamines and ω-phenylalkylamides in carbon tetrachloride and α,α,α-trifluorotoluene

¹³C, ¹³C coupling constants and ¹³C chemical shifts of aromatic carbonyl compounds. Effects of ortho‐ and peri‐interactions involving the carbonyl substituent

An Immobilized Homogeneous Catalyst for Efficient and Selective Hydrogenation of Functionalized Aldehydes, Alkenes, and Alkynes

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Structural determination of monosubstituted alkylbenzenes by proton magnetic resonance

Cited by 15 publications

References 26 publications

Aromatic chlorination of ω-phenylalkylamines and ω-phenylalkylamides in carbon tetrachloride and α,α,α-trifluorotoluene

Aromatic chlorination of ω-phenylalkylamines and ω-phenylalkylamides in carbon tetrachloride and α,α,α-trifluorotoluene

13C, 13C coupling constants and 13C chemical shifts of aromatic carbonyl compounds. Effects of ortho‐ and peri‐interactions involving the carbonyl substituent

An Immobilized Homogeneous Catalyst for Efficient and Selective Hydrogenation of Functionalized Aldehydes, Alkenes, and Alkynes

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¹³C, ¹³C coupling constants and ¹³C chemical shifts of aromatic carbonyl compounds. Effects of ortho‐ and peri‐interactions involving the carbonyl substituent