(Z)-Stereospecific Addition of Glycosylmercaptans on Nitrilium Betaines.1Synthesis of 1-S-Glucopyranosyl Arylthiohydroximates
摘要:
With a view to selecting new internal standards for HPLC analysis of glucosinolates, the synthesis of artificial desulfoglucosinolates 5 was carried out.
Convenient synthesis of isoxazolines via tandem isomerization of allyl compounds to vinylic derivatives and 1,3-dipolar cycloaddition of nitrile oxides to the vinylic compounds
effective method for the synthesis of new isoxazolines via tandem isomerization of QCH(X)CHCH(Y) to QC(X)CHCH2(Y) (Q = RO, RS, R2N, R3Si, etc.; X = H, R, OR; Y = H, R; R = alkyl, aryl) catalyzed by ruthenium complexes and 1,3-dipolar cycloaddition of the latter compounds to arenenitrile oxides is presented. The cycloaddition of QCH(X)CHCH(Y) to 2,6-dichlorobenzonitrile oxide is also described. The regio-
通过将QCH(X)CHCH(Y)串联异构化为QC(X)CHCH 2(Y)(Q = RO,RS,R 2 N,R 3 Si等; X = H,R,OR; Y = H,R; R =烷基,芳基)被钌配合物催化,并且提出了后者化合物的1,3-偶极环加成成芳族腈氧化物。还描述了QCH(X)CHCH(Y)与2,6-二氯苄腈氧化物的环加成。讨论了氮氧化物与烯丙基和1-丙烯基(通常为乙烯基)化合物的环加成反应的区域选择性和立体选择性。
Synthesis of 5-aminoisoxazolines from N-allyl compounds and nitrile oxides via tandem isomerization-1,3-dipolar cycloaddition
5-aminoisoxazolines via tandem catalytic isomerization (of N-allyl systems to N-(1-propenyl) systems)—1,3-dipolar cycloaddition (of a stable nitrileoxide to N-(1-propenyl) systems) is presented. Rhodium and ruthenium complexes, Verkade’s superbase, and 18-crown-6/KOH system were used for the syntheses of the N-(1-propenyl) systems. 4-P-substituted isoxazoline was also synthesized via cycloaddition of
Δ<sup>2</sup>-Isoxazoline derivatives. Part X. 1,3-Dipolar cycloadditions of nitrones and nitrile oxides with indene, 1,2-dihydronaphthalene, and trans-1-phenylpropene
作者:Giorgio Bianchi、Carlo De Micheli、Remo Gandolfi
DOI:10.1039/p19760001518
日期:——
Reactions of cyclic and acyclic nitrones and nitrileoxides with 1,2-dihydronaphthalene, indene, and trans-1-phenylpropene give rise to mixtures of regioisomers. The results are analysed on the basis of frontier orbital interactions and the steric requirements of reagents.