An efficient synthesis of 4‐(<i>N</i>,<i>N</i>‐diallylamino)pyridines

Huang, Jitao; Sun, Jinsheng; Liu, Zhenghua

doi:10.1002/app.1995.070561311

Cited by 3 publications

(2 citation statements)

References 6 publications

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“…Presumably, the increased nucleophilicity of the pyridyl nitrogen in amine 20 , as compared to its Boc-deactivated analogues 10 and 11 , makes quaternization of the substrate/product a significant side-reaction. Since intermolecular alkylations of 4-monoalkylaminopyridine anions are known to proceed selectively on the exocyclic nitrogen, it was anticipated that conversion of the hydroxyl group in amino alcohol 20 to a good leaving group with concomitant deprotonation of the amine would improve the yield of the process. Indeed, treatment of the alkoxide of aminol 20 with ( N -methylphenylamino)triphenylphosphonium iodide (Murahashi's reagent), gave the desired product in good yield.…”

Section: Resultsmentioning

confidence: 99%

Configurationally Stable Biaryl Analogues of 4-(Dimethylamino)pyridine: A Novel Class of Chiral Nucleophilic Catalysts

et al. 1999

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A short synthetic approach toward a novel class of chiral nucleophilic catalysts, the dissymmetry of which stems from restricted rotation about an Ar-Ar bond, has been developed. The key steps of the synthesis include preparation of a nucleophilic 1-methyl-2-pyrrolino[3,2-c]pyridine core 16 by ortho-lithiation and creation of the biaryl axes via Suzuki cross-coupling reactions. Comparative HPLC studies of racemization for configurationally labile biaryls 31, 38, and 43 containing 1-methyl-2-pyrrolino[3,2-c]pyridine, 4-(dimethylamino)pyridine, and 4-(1-pyrrolidino)pyridine cores, respectively, have demonstrated that a pyrrolidino substituent ortho to the biaryl axis is optimal for slowing Ar-Ar rotation. Biaryls containing all three cores have been shown to retain DMAP-like catalytic activity in the acylation of a hindered alcohol. Biaryls 55 and 56, which are configurationally stable at ambient temperature, have also been prepared via modification of configurationally labile derivatives. Compounds 55 and 56 in optically pure form should provide a useful starting point for studies on catalytic asymmetric acyl transfer using atropisomeric analogues of DMAP.

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Section: Resultsmentioning

confidence: 99%

Configurationally Stable Biaryl Analogues of 4-(Dimethylamino)pyridine: A Novel Class of Chiral Nucleophilic Catalysts

et al. 1999

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“…The synthesis of N-substituted 2,5-bis(alkoxymethyl)pyrrolidines (and isostructural borolanes 50 and phospholanes 51-53 ) from enantiomerically pure 1,4-dimesylates, 54, 55 1,4-ditosylates, 55- 57 1,4-ditriflates, 55,58,59 and 1,4-cyclic sulfates 51 by cyclocondensation with primary amines is well known. 60 The feasibility of employing poorly nucleophilic 4-aminopyridine was first established by a cyclocondensation reaction between 2,5-bis-(methylsulfonyloxy)hexane 10 and the disodium salt of 4aminopyridine 61 to give a ~1 : 1 mixture of PPYs (±)-9 and 12 in 98% yield (Scheme 1). ¶ For the synthesis of chiral PPYs I an efficient synthesis of enantiomerically pure tetrol 11a 56,57,62 was required.…”

Section: Resultsmentioning

confidence: 99%