摘要:

Aptitude to ring expansion in the piperidine series, measured by the ratio of ring expanded ketone to epoxide, varies considerably according to the nitrogen atom substituent. This ratio is essentially the same in the case of the reaction of diazomethane on 4-piperidones and the nitrous acid deamination of the corresponding aminoalcohols. The values of the ratio are 0.01–0.1 for a phenylsulfonyl group, of the order 0.3–0.6 for a benzoyl group and slightly greater than 1 for a benzyl group. Electronic effects (inductive and field effects) are the cause of these differences. Parallels between the two reactions indicate that nucleophilic attack of diazomethane on the carbonyl group can lead to the ring expanded ketone and the epoxide.

ISSN:0008-4042    

DOI:10.1139/v71-516

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

Nitrous acid deamination ofcis-1-aminomethyl-4-phenylsulfonyl-1-cyclohexanol gives 60% of epoxide and 23% of ring-expanded ketone whereas thetransisomer gives 28% of epoxide and 60% of ring-expanded ketone. The large proportion of epoxide is accounted for by the inductive effect and the field effect of the phenylsulfonyl group; a conformational effect wherein the CH2NH2group leads to more epoxide when in an equatorial conformation than in an axial is also observed in this reaction. This study required the preparation of 4-phenylthio and 4-phenylsulfonyl cyclohexanols andcis- andtrans-1-methyl cyclohexanols.

ISSN:0008-4042    

DOI:10.1139/v71-517

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

This paper describes the reaction of diazomethane generatedin situ,methanolic potassium hydroxide solution, on 4-phenylsulfonyl, 4-tert-butyl, and 4-phenylthio-cyclohexanones. In the latter two cases, the reaction leads to mixtures containing mostly the enlarged ketones along with minor quantities of the corresponding epoxides. In the first case, the enlarged ketone and the corresponding epoxides are formed in equal amounts. This marked increase in the production of epoxides is indicative of transannular interactions between the sulfonyl group and the intermediate betaine. In theex situreactions, methanolic solutions without potassium hydroxide, phenylsulfonylcyclohexanone yields the corresponding dimethyl acetal almost exclusively whereas the tert-butyl and phenylthioketones follow the same course as in thein situreactions. Furthermore, it has been observed in all cases that, under the conditions used, the potassium hydroxide leads to opening of the epoxide rings to yield hydroxy-ethers of the typeCH2—O—CH3. This epoxide-ring-opening was advantageously used in the preparation of pure epoxides from epimeric mixtures. The epoxides generated from the three ketones studied are mixtures ofcis-transisomers, rich incisepimer.

ISSN:0008-4042    

DOI:10.1139/v71-518

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

The ultrasonic absorption of dimethyl sulfoxide solutions of several alkali halides has been studied in the frequency range 1.5 to 52 MHz. An excess absorption, relaxing between 3 and 8 MHz, was observed. The relaxation was assigned to the final step in the stepwise formation of a contact ion pair, with the relaxation frequency controlled by the rate of movement of a solvent molecule rather than an ion. Data on the system water – dimethyl sulfoxide are also presented and the effect of water on the relaxation discussed.

ISSN:0008-4042    

DOI:10.1139/v71-519

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

The solubility of mercury in water has been determined between 4 and 72 °C. Standard thermodynamic functions have been evaluated for mercury transfer from the liquid metal to aqueous solution and from aqueous solution to the gas phase. Mercury in water exhibits large positive deviations from Raoult's Law and shows a high relative volatility of 15 400 at 25 °C.

ISSN:0008-4042    

DOI:10.1139/v71-520

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

Diphenylcyclopropenethione reacts with a variety of heteroaromatic nitrogen compounds to give in excellent yields four types of products (a) 6,7-diphenyl-8-thionpyrazolo[1,2-a]pyridazine and -cinnolines, (b) azaindolizinthiols, (c) azaindolizine disulfides, and (d) 1-methoxy-1,2-diphenyl-3-thionpyrrolidino-[1,2-a]isoquinoline and similar structures. Proof of structure of products of typearests on their independent synthesis by the action of phosphorus pentasulfide on the known oxo-analogs. Products of typebare converted readily into typecby air oxidation. In products of typeda molecule of solvent methanol is incorporated in the structures.

ISSN:0008-4042    

DOI:10.1139/v71-521

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

The polarographic reduction of the ozonides of stilbene and of selected ring-substituted styrenes, yielding 2 mol of aldehyde per mole of ozonide, has been studied. With the substituted styrenes a Hammett relationship is observed for the half-wave potentials. The positive ρ constant (0.20) indicates that the determining step is a nucleophilic process. Possible mechanisms are discussed.

ISSN:0008-4042    

DOI:10.1139/v71-522

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

A series of 6-substituted cyclodecynes has been synthesized and the transannular cyclizations of these compounds were studied. The observed transannular cyclizations were highly stereoselective and give products containing the bicyclo [4.4.0] decane skeleton.

ISSN:0008-4042    

DOI:10.1139/v71-523

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

Data from the p.m.r. spectra of β-amino-, β-aminohydrochloride-, β-hydroxy-, and β-nitro-α-phenyl-propanes having methyl or methoxy substituants on the phenyl ring (37 compounds in all) are presented. The α and β protons of the side-chain give a pattern usually analyzable as ABX. The data are discussed in terms of correlations of coupling constants and chemical shifts with electronegativity of the substituent groups, steric and electronic effects, and apparent changes in rotamer populations. Hydrogen-bonding between the amino group of amphetamines and a methoxyl function at the ortho position in the phenyl ring is indicated for the salts but not the free bases.

ISSN:0008-4042    

DOI:10.1139/v71-524

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

The AlCl3-promoted reactions of 2-methyl- and of 2-phenylfuran with ethyl propiolate afford as major products ethyl 5-hydroxy-2-methyl- and 2-phenylbenzoates (6a,6b). Also isolated as minor by-products of these reactions are ethyl 3-(2-furyl-5-methyl)acrylate (5a), ethyl 3-(2-furyl-5-phenyl)acrylate (5b), ethyl 3,3-di(2-furyl-5-methyl)propionate (10a), ethyl 3,3-di(2-furyl-5-phenyl)propionate (10b), and ethyl 2-hydroxy-5-methylbenzoate (8a).

ISSN:0008-4042    

DOI:10.1139/v71-525

出版商:NRC Research Press    

年代:1971

数据来源: NRC