The reactions of simple dimethylallylamines with dimethyl acetylenedicarboxylate. Formation of 1-dimethylamino-2-allylmaleates via formal allyl transfer

Abstract

. Can. J. Chem. 66, 1686 (1988). Tertiary amines bearing two methyl groups and an allylic substituent (X) react with dimethyl acetylenedicarboxylate (DMAD) to afford the corresponding 1-dimethylamino-2-X' maleates, in which X' is the allylic isomer of X. The mechanism postulated involves reversible formation of a zwitterion by attack of the amine at an sp-carbon of DMAD. The zwitterion then undergoes intramolecular allyl transfer, through a 6-membered transition state. Evidence for a zwitterionic intermediate (quaternary ammonium allenolate) includes capture of the allenolate centre by intramolecular addition to a carbonyl group and by proton transfer from chloroform. ADRIAN L. SCHWAN et JOHN WARKENTIN. Can. J. Chem. 66, 1686 (1988). Les amines tertiaires qui portent deux groupements mCthyles et un substituant allylique (X) rtagissent avec I'acCtyltnedicarboxylate de dimCthyle (ADDM) pour fournir les maleates correspondants, dimtthylamino-l XI-2 malCates, dans lesquels le groupement X' est I'isomkre allylique de X. Le mecanisme postulC implique la formation reversible d'un zwitterion par I'attaque de I'amine sur le carbone-sp de I'ADDM. Le zwitterion subit alors un transfert allylique intramoleculaire par le biais d'un Ctat de transition a six chainons. Les donntes supportant I'hypothkse de I'existence d'un zwitterion comme intermediaire (allknolate d'ammonium quaternaire) comportent la capture du centre allbnolate par une addition intramoleculaire sur un groupement carbonyle ainsi qu'un transfert de proton B partir du chloroforme.[Traduit par la revue]

Dimethyl 2-[23-oxo-22,24-diphenyl-8,11,14-trioxa-25-azatetracyclo[19.3.1.02,7.015,20]pentacosa-2,4,6,15(20),16,18-hexaen-25-yl]but-2-enedioate

“…The expected reaction is well known (Schwan & Warkentin, 1988), but might be highly hindered due to the steric reasons. We have found, however, that the expected N-vynilation proceeded smoothly with the formation of an Nmaleinate derivative of the azacrown system.…”

“…For general background to the design, synthesis, chemical properties and applications of macrocyclic ligands in coordination chemistry, see: Hiraoka (1978); Pedersen (1988); Schwan & Warkentin (1988); Gokel & Murillo (1996); Bradshaw & Izatt (1997). For related compounds, see: Levov et al (2006Levov et al ( , 2008; Anh et al (2008); Hieu et al (2011); Khieu et al (2011).…”

Uncommon expansion of piperidine ring into hydroazocine ring in reactions of some piperidine β-acyl derivatives with acetylenecarboxylic acids esters

“…The racemic crystal of compound 1 consists of enantiomeric pairs of diastreomers with the relative configuration of the chiral centers rac-4S*,4аS*,8аS*. In the study of chemical modification of compound 1 by the reaction with acetylenecarboxylic ester (aiming at its N-demethylation [9,10], N-vinylation [10,11], and cyclization at the carbonyl carbon atom [10][11][12][13]) we discovered a quite unexpected transformation of the piperidine ring in an eight-membered cycle with the formation of compound 2 isolated by chromatography in 23% yield. The structure of compound 2 was confirmed by spectral data.…”

Unexpected cascade synthesis of 1-azabicyclo[3.3.1]nonanes by nucleophilic reaction of bis(2-aroylethyl)methanamines with dimethyl acetylenedicarboxylate

“…Presumably, the cascade process begins with attack by amine 1 or 2 on the activated triple bond of dimethyl 1, 3, R = Ph; 2, 4, R = thiophen-2-yl. [1], analogous oxygen-centered anion immediately abstracted proton from chloroform (solvent) or deuteron from CDCl 3 , and elimination of one methyl group from the nitrogen atom afforded the final product, 1-methyl-4-phenyl-1,2,3,4-tetrahydropyridin-4-ol. We failed to detect analogous tetrahydropyridinols in the reaction mixture by HPLC/MS.…”

“…IR spectrum: ν 1747 cm -1 (C=O). 1 The 1 H NMR spectra were recorded on a Bruker WP-400 spectrometer at 400 MHz. The IR spectra were measured in KBr on an Infralyum FT-801 spectrometer.…”