摘要:

AbstractThe synthesis of 4‐formyl‐3‐hydroxy‐5‐methacryloylaminomethyl‐2‐methylpyridine (7a) and 4‐formyl‐3‐hydroxy‐5‐(N‐methacryloyl‐N‐methyl)aminomethyl‐2‐methylpyridine (7b) is reported. The intermediate products 5‐aminomethyl‐2,2,8‐trimethyl‐2H,4H‐[1,3]‐dioxino[4,5‐c]‐pyridine hydrochloride (3a), 2,2,8‐trimethyl‐5‐methylaminomethyl‐2H,4H‐[1,3]‐dioxino[4,5‐c]‐pyridine hydrochloride (3b), 5‐methacryloylaminomethyl‐2,2,8‐trimethyl‐2H,4H‐[1,3]‐dioxino‐[4,5‐c]pyridine hydrochloride (5a), 5‐(N‐methacryloyl‐N‐methyl)aminomethyl‐2,2,8‐trimethyl‐2H,4H‐[1,3]‐dioxino‐[4,5‐c]pyridine hydrochloride (5b), 3‐hydroxy‐4‐hydroxymethyl‐5‐metha‐cryloylaminomethyl‐2‐methylpyridine (6a)

ISSN:0025-116X    

DOI:10.1002/macp.1983.021840101

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractN‐(4‐vinylbenzyl)‐L‐histidine (5) and the corresponding methyl ester were synthesized by reactingL‐histidine orL‐histidine methyl ester with 4‐formylstyrene.N‐(4‐vinylbenzyl)‐L‐histidine methyl ester was radically copolymerized with various amounts of 2‐hydroxyethyl methacrylate and ethylene dimethacrylate, leading to resins of different degrees of hydrophilicity and crosslinking. After saponification of the histidine ester groups, the resins were chelated with Ni2+salt in order to be used as polymeric catalysts in enantioselective est

ISSN:0025-116X    

DOI:10.1002/macp.1983.021840102

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractThe kinetics of hydrolysis of D‐ and L‐histidine methyl ester were studied in the presence of crosslinked hydrophilic polymeric supports bearing L‐histidine moieties complexed with Ni2+salt. The selectivity of hydrolysis (kD/kLratio) rises with the increase of the hydrophilic character (content of monomeric units of 2‐hydroxyethyl methacrylate) of the resin. It varies with the ratio ester / catalytic moiety, the best result being obtained when the latter is close to 1. The selectivity depends on the temperature and an inversion of this selectivity is observed at 31°C. The optimization of all the parameters studied allowed to reach the same enantioselectivity and comparable rates of hydrolysis as observed in a model reaction carried out under homogeneous co

ISSN:0025-116X    

DOI:10.1002/macp.1983.021840103

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractThe paper presents a study of the radical polymerization of cyclohexyl acrylate (CHA) in the presence of ZnCl2. It was found by IR,1H NMR, and13C NMR spectroscopy that a complex of ZnCl2with CHA is formed. For copolymerization of CHA with vinylidene chloride, both theQ‐ ande‐value of CHA increased with the ZnCl2concentration. The initiation rate andk p2/ktwere determined using DPPH as an inhibitor. It was found that ZnCl2did not affect the initiation rate. Thekpvalue of CHA was determined to be about 2720 1 · mol−1· s−1in the absence and 4710 1 · mol−1· s−1in the presence of ZnCl2by the rotating sector method. The enhanced polymerization rate of CHA in the presence of ZnCl2can be ascribed to the largekpvalue. The termination rate constant is not significantly affected by the

ISSN:0025-116X    

DOI:10.1002/macp.1983.021840104

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractThe anionic polymerization of 2‐pyrrolidone (3) initiated with its potassium salt (1) (2‐oxo‐1‐pyrrolidinylpotassium) and carbon dioxide was studied under optimal conditions. On the basis of a detailed experimental analysis, it is suggested to consider the investigated polymerization in the presence of gaseous CO2as an accelerated non‐activated polymerization. Alkali 2‐oxo‐1‐pyrrolidine carboxylate, which is formed in the system by reaction of CO2with1, probably does not take part directly in the polymerization process and excerts only a c

ISSN:0025-116X    

DOI:10.1002/macp.1983.021840105

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractIntrinsic viscosities inm‐cresol and weight average molecular weights,M̄w, were measured for samples of high molecular weight poly(2‐pyrrolidone) (poly (1)) prepared by anionic polymerization of 2‐pyrrolidone (1) accelerated with CO2. It was proved that the earlier found relationship [η] = 4 · 10−2·M0,77(in cm3· g−1) holds for M̄Mwup to 8 · 105g. mol−1. The probable reason for the formation of poly (1) with an exceptionally high molecular w

ISSN:0025-116X    

DOI:10.1002/macp.1983.021840106

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractThermal dimerization of methyl acrylate to dimethyl 2‐methyleneglutarate was performed in a high pressure‐high temperature flow apparatus at temperatures up to 420°C and pressures up to 200 bar. The head to head dimer dimethyl 2‐methyl‐3‐methylenesuccinate was observed, too. Methyl vinyl ketone and acrylonitrile are able to dimerize a

ISSN:0025-116X    

DOI:10.1002/macp.1983.021840107

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

Abstract5‐Hydroxy‐7‐methoxy‐2,2‐dimethyl‐6‐octyl(and 8‐octyl)‐4‐chromanones (2aand2b) were synthesized via 5,7 dihydroxy‐2,2‐dimethyl‐6‐octyl (and 8‐octyl)‐4‐chromanones (1aand1b) from phloroglucinol as a starting material. Cyclohexane solutions of1a, 1b, 2a, and2bwere irradiated. The photostability of2aand2bwas found to be better than that of1aand1b. Poly(vinyl chloride) film containing 6, 7 wt.‐% of2bwas found to be

ISSN:0025-116X    

DOI:10.1002/macp.1983.021840108

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractThe equilibrium in the system containing hexamethyldisiloxane, trifluoroacetic acid, and the inert solvent methylene chloride is studied. The system may serve as a model of reactions which play an important role in the cationic polymerization of cyclic siloxanes. The kinetic studies confirm that analogous reactions control the concentrations of silanol and silyl ester end groups as well as of acid and water during the polymerization. Allowing for some hydrogen bonding formation in the analysis of these equilibria the respective equilibrium constants can be obtained preserving almost constant values in the total range of concentrations studied.

ISSN:0025-116X    

DOI:10.1002/macp.1983.021840109

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractIn this paper, the distribution of configurational sequences in vinyl polymers is re‐treated theoretically by the aid of statistics. Various Markovian probabilities of multi‐ads are listed. A series of relationships among the frequencies of occurrence of n‐ads with different configurations is obtained, most of them have not been reported up to now. Finally, a convenient method for determination of the order of a Markovian process is establ

ISSN:0025-116X    

DOI:10.1002/macp.1983.021840110

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY