1,3-Dipolare cycloadditionen von 6,7-dialkoxy-3,4-dihydroisochinolinium-Salzen

Bende, Z.; Tőke, Lásʐló; Weber, Lutz; Tóth, Gábor; Janke, F.; Csonka, Gábor I.

doi:10.1016/s0040-4020(01)91183-4

Cited by 25 publications

(9 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The CH group signal is absent in the spectrum of base 4 which points to an enamine structure. The spectra of bases 5-7 were identified by agreement with the data in [4,5]. The condensed tricyclic structure for the materials obtained was confirmed by the presence of four CH group doublets, two of which (2.10-2.15 ppm and 3.13-3.15 ppm) in positions 1 and 2 are complicated by the occurrence of interaction with the protons at positions 3 and 10b.…”

supporting

confidence: 71%

“…It should be noted that most of the reactions of this type reported in the literature relate to heteroaromatic systems. The few examples of the use of 3,4-dihydroisquinolines in this reaction are given in the studies [4,5]. A feature of compounds 2a-d is their stability upon storage which makes them suitable as reagents.…”

mentioning

confidence: 99%

“…Similarly, the reaction of the ylide prepared from iodide 2d with dimethylmaleate gives amide 7. According to generally available data [4][5][6] dipolar cycloaddition reactions occur stereospecifically, i.e. in the case of dimethylmaleate to give the cis-isomer and for dimethylfumarate the trans isomer as a mixture of exo and endo forms [5].…”

mentioning

confidence: 99%

See 2 more Smart Citations

Properties of 3,3-dialkyl-3,4-dihydro-isoquinoline cyclic azomethines

Surikov

Михайловский

Вахрин

2009

Chem Heterocycl Comp

View full text Add to dashboard Cite

The reactions of 3,3-dialkyl-3,4-dihydroisoquinoline cyclic azomethines with the methyl ester and p-toluidide of iodoacetic acid gave stable quaternary ammonium salts which were suitable dipoles for [3+2] cycloaddition reactions. Azomethines activated by iodomethylation react with potassium cyanide and malonodinitrile.Keywords: 3,3-dialkyl-3,4-dihydroisoquinolines, methyl ester and p-toluidide of iodoacetic acid, quaternary ammonium salts, dipolar [3+2] cycloaddition, reaction with potassium cyanide and malonodinitrile.Amongst cyclic azomethines isoquinoline derivatives [1] have greatest value in organic synthesis. We have previously prepared 3,3-dialkyl-3,4-dihydroisoquinoline cyclic azomethines [2,3]. The chemical properties of these compounds have been little studied up to this time. The aim of our work was to study their reaction with nucleophiles. The goal of the work was also to clarify the use of the named cyclic imine salts as potential dipoles in [3+2] cycloaddition reactions.Studies have shown that compounds 1a-c react with methyl iodoacetate to form the stable iodides 2a-c. The base 1c forms salt 2d similarly with iodoacetic acid p-toluidide. A study of the properties of compounds 1a-c has shown that bases of these cyclic azomethines do not react with C-nucleophiles like KCN or malonodinitrile without activation. The desired result can be achieved by activation of the imino group via iodomethylation. Hence reaction of the iodomethylate of imine 1c with potassium cyanide in alcohol gives the tetrahydroisoquinoline 3 which was characterized as the hydroiodide. The reaction of this compound with malonodinitrile occurs in the presence of sodium methylate in methanol to give the dinitrile 4. In the absence of the MeONa the reaction mixture yielded only the starting material. R 1 R 1 N R R N O OMe ICH 2 C(O)OMe 1a-c 2a-c + I -1,2 a,b R = H, c R = MeO; 1a,c, 2a R 1 = Me; 1, 2 b R = (CH 2 ) 5 , 2c R 1 = Me

show abstract

supporting

confidence: 71%

mentioning

confidence: 99%

See 1 more Smart Citation

Properties of 3,3-dialkyl-3,4-dihydro-isoquinoline cyclic azomethines

Surikov

Михайловский

Вахрин

2009

Chem Heterocycl Comp

View full text Add to dashboard Cite

show abstract

“…The regioselectivity and stereochernistry of the addition of imines to compounds of type 79 were substantiated by PMO theory using CNDO/2 and CNDO/S approaches. The ratio of endo/exo isomers was considered [213,214].…”

Section: O N ~N P H 0-75 76mentioning

confidence: 99%

Cyclic azomethines and their hydrogenated derivatives. (Review)

Михайловский¹

2000

Chem Heterocycl Compd

View full text Add to dashboard Cite

show abstract

“…The authors explain the selectivity of the process by the fact that the reaction takes place as endo-addition of the dipolarophile molecule to the ant/-form of the ylide through a five-center transition state [112] with the conservation of orbital symmetry. Investigations showed the successful application of the 3,4-dihydroisoquinoline system for the same purposes [114][115][116][117][118]. Investigations showed the successful application of the 3,4-dihydroisoquinoline system for the same purposes [114][115][116][117][118].…”

Section: Nc XLIVmentioning

confidence: 99%