Benzyl chloride, structure

Hammen equation A correlation between the structure and reactivity in the side chain derivatives of aromatic compounds. Its derivation follows from many comparisons between rate constants for various reactions and the equilibrium constants for other reactions, or other functions of molecules which can be measured (e g. the i.r. carbonyl group stretching frequency). For example the dissociation constants of a series of para substituted (O2N —, MeO —, Cl —, etc.) benzoic acids correlate with the rate constant k for the alkaline hydrolysis of para substituted benzyl chlorides. If log Kq is plotted against log k, the data fall on a straight line. Similar results are obtained for meta substituted derivatives but not for orthosubstituted derivatives. 

The syntheses of these initiators is described in Sect. II.C. According to detailed H1 NMR analysis hydrosilylation yielded 15-20% isomers along with the major products 1, 2, and 3 as shown in Figs. 1-3. The presence of the isomers, listed in Table 1, should not affect initiating efficiency by the benzyl chloride group, in view of the structure and virtually identical H1 NMR chemical shifts of the chloromethyl groups. 

Knochel et al. (1977a) have studied the effect of the structure of the ligand on its ability to catalyse the reaction between solid metal acetates and benzyl chloride dissolved in acetonitrile. Approximate half-lives for the reactions are given in Table 29. For crown ethers, the reactivity sequence decreases in the... 

Fig. 13 The relative structures for the SN2 transition states for the reactions of p-substituted benzyl chlorides with cyanide ion. Reproduced, with permission, from...

Gas-phase nucleophilic substitution reactions of Y-benzyl chlorides and X-phenoxide or X-thiophenoxide nucleophiles have been investigated by using the PM3 semiempirical MO method. The structure of the transition state was examined. The values of the gas-phase Hammett constants px and py are much greater than for the solution reactions, but a theoretical cross-interaction constant pxy (ca —0.60 for both phenoxides and thiophenoxides) agrees well with an experimental value of —0.62 for the thiophenoxide reactions in MeOH at 20 °C. Other work by the same group has involved theoretical studies of competitive gas-phase 5 n2 and E2 reactions of NCCH2CH2CI with HO and An ab initio method at the 6-31-l-G level was... 

The low structural specificity of the antihistamines has already been noted. It is perhaps not too surprising, therefore, to find Lhat attachment of the basic side chain directly onto one of the. iromatic rings affords active compounds. In an unusual reaction reminiscent of the Claisen rearrangement, benzyl chloride affords the substituted phenol, 46, on heating with phenol itself. Alkyl-.ition of 46 with 2-dimethylaminoethyl chloride gives phenyltolox-.imine (47).Alkylation of that same intermediate (46) with 1-bromo-2-chloropropane, leads to 48. Use of that halide to alkyl-,ite piperidine gives the antihistamine, pirexyl (49). ... 

A series of pyrido[2,3-rf pyrimidine-2,4-diones bearing substituents at C-5 and/or C-6 were synthesized using palladium-catalyzed coupling of uracil derivative 417 with vinyl substrates or allyl ethers to give the regioisomeric mixtures of 418/419 and 420/421, respectively. The ratio of the isomeric structures was dependent on the substituent R. In the case of the reaction with -butyl vinyl ether, only the product 419 was obtained. However, the reactions with acrylonitrile, ethyl acrylate, 2-trifluoromethylstyrene, and 3-nitrostyrene afforded only 418. Also, reaction with allyl phenyl ether gave only 420. The key intermediate 417 was prepared by the reaction of 6-amino-l-methyluracil with DMF-DMA (DMA = dimethylacetamide), followed by N-benzylation with benzyl chloride and vinyl iodination with iV-iodosuccinimide (NIS) (Scheme 15) <2001BML611>. 

Kinetics and Mechanism of Reactions of Bis (methyl-2,2 -dimercaptodiethyl-amine) dinickel(II) with Alkyl Halides. The rates of reaction of [Ni2 CH3N-(CH2CH2S)2 2], structure III, with methyl iodide, benzyl bromide, benzyl chloride, p-chlorobenzyl chloride, and p-nitrobenzyl chloride have been studied as functions of temperature and concentration in chloroform (3). Absorbance measurements were utilized to determine the rates. All experiments were conducted with excess alkyl halide (20 to 1000 times the initial concentration of complex). Jicha and Busch (18) were able to isolate alkylated complexes of the composition... 

Pyrazolo[4,3-c]pyridines gave 5-methiodides in excellent yield.144 154 A methiodide of pyrazolo[l,5-a]pyridine 199b (R1 = H) was also prepared but its structure was not assigned161 the parent compound 5 quaternized in the 1-position.209 The saturated amide, however, formed a 7a-quaternary salt (263) with benzyl chloride, which was converted to the 1-benzyl derivative via the internal salt 264.209... 

The vapor heat capacities of hronmhcnzene, chlorobenzene. and fluorobcnzcnc have been reported in (be liter -turevr 1 ITk data lor benzyl chloride were exit muted from its molecular structure T Above StKfC. the error should be less than ... 

Kotarska et a/.106-282 attributed the 3-substituted structures to the products obtained from the pyrido[l,2-a]pyrimidine (63 R = H) by alkylation with either 1-chloromethylnaphthalene or allyl bromide, or with benzyl chloride in ethanolic potassium hydroxide in the presence of potassium iodide. The melting point of the 3-benzyl compound agreed with the earlier literature datum but that of the 3-allyl compound differed by more than 20 C.100,112... 

Suggest a mechanism for this transformation and predict the structure of the product that would be formed if the same concept were applied to the condensation of 2-(trifluoromethyl)benzyl chloride with 2-benzo[h]thienyllithium. 

A 5-benzyl-D-ribose has been prepared by Kenner, Taylor and Todd,90 who etherified the methyl 2,3-isopropylidene-D-ribofuranoside (XXI) of Levene and Stiller91 with benzyl chloride to obtain methyl 2,3-iso-propylidene-5-benzyl-D-ribofuranoside (XXII), which was subsequently hydrolyzed to give amorphous 5-benzyl-D-ribose (XXIII). The structure of this ether was confirmed through acetylation to its triacetate (XXIV), hydrogenolysis to 1,2,3-triacetyl-D-ribofuranose (XXV) and further acetylation to the known, crystalline tetraacetyl-D-ribofuranose (XXVI). 

In the reaction of 3-nitro-177-1,2,4-triazole with benzyl chloride it was possible to obtain l-benzyl-3-nitro-177-l,2,4-triazole (60%), l-benzyl-5-nitro-17/-l,2,4-triazole (10%), and 4-benzyl-3-nitro-177-l,2,4-triazole (4%), whose structures were determined by H and 13C NMR with homonuclear NOE difference spectroscopy (Table 3.21) [559], The tautomerism of C-nitro-substituted 1,2,4-triazoles was studied by NMR and IR spectroscopy [582], 31P NMR spectroscopy was employed for the identification of nitrated triazolyl-1 phosphates [583, 584],... 

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