3533-63-9Relevant academic research and scientific papers
Silylamination of electrophilic alkynes
Baines, Kim M.,McOnie, Sarah L.
supporting information, (2021/12/23)
The addition of simple silylamines to dialkyl acetylenecarboxylates was investigated yielding both E and Z-silylenamines in contrast to an earlier report. Silylamination was also achieved with propiolates, expanding the scope of the silylamination reactio
1,3-Diaza-1,3-butadienes. Synthesis and conversion into pyrimidines by [4π + 2π] cycloaddition with electron deficient acetylenes. Synthetic utility of 2-(trichloromethyl)pyrimidines
Guzman,Romero,Talamas,Villena,Greenhouse,Muchowski
, p. 2470 - 2483 (2007/10/03)
Methods have been devised to generate 1H-1,3-diaza-1,3-butadienes bearing a leaving group at position-4 in latent, masked, and unprotected forms. A hallmark of these azadienes is that they undergo thermal [4π ± 2π] cycloaddition reactions with electron deficient acetylenes to give adducts which are aromatized to pyrimidine derivatives under the reaction conditions. Thus, 1-(methoxycarbonyl)-3-acylamidines 17 on heating in solution are converted in situ into the 1,3-diaza-1,3-dienes 18 and/or 19 which react with dimethyl acetylenedicarboxylate (DMAD) to produce the pyrimidines 26. The 1-Boc-1,3-diaza-1,3-dienes 24 are masked forms of the 1H-dienes inasmuch as they react with DMAD under relatively mild conditions to give the dihydropyrimidine adducts 25, which are easily detectable by 1H NMR spectroscopy, and which aromatize to pyrimidines 20 at higher temperatures. The 4-methylthio compounds 31 and 33, and the 2-(trichloromethyl) compounds 37, are isolable, relatively stable, 1H-1,3-diaza-1,3-butadienes. These easily prepared compounds react with electron deficient acetylenes under mild conditions to provide the pyrimidines 20, 34, and 38, respectively, in fair to excellent yields. The 2-(trichloromethyl)pyrimidines 38 are very useful precursors of a wide variety of other 2-substituted pyrimidines 46-52.
Thermal Reactions of 6-Methyl-5--2,4(1H,3H)-pyrimidinediones with Electron-Deficient Olefins and Acetylene
Noguchi, Michihiko,Kiriki, Yasutoshi,Tsuruoka, Takashi,Mizui, Takahiro,Kajigaeshi, Shoji
, p. 99 - 105 (2007/10/02)
The thermal reactions of some 6-methyl-5--2,4(1H,3H)-pyrimidinediones (1) were investigated.The 1,5-hydrogen shift in 1 gave 5,6-dihydro-5,6-bis(methylene)-2,4(1H,3H)-pyrimidinedione intermediates, while the 1,2-hydrogen shi
THE REACTIVITY OF 2-FORMYLTHIOPHENE, 1-METHYL-2-FORMYLPYRROLE, BENZALDEHYDE AND 2-FORMYLFURANE N,N-DIMETHYLHYDRAZONES WITH DIMETHYL ACETYLENEDICARBOXYLATE
Gonzalez, M. Eugenia,Sancho, Pedro,Soriano, Concepcion,Ballesteros, Rafael,Abarca, Belen,Sepulveda, Jose
, p. 1227 - 1232 (2007/10/02)
N,N-Dimethylhydrazones derived from 2-formylthiophene, benzaldehyde, and 1-methyl-2-formylpyrrole react with dimethyl acetylenedicarboxylate (DMAD), giving the corresponding nitriles.The reaction with furfural N,N-dimethylhydrazone takes place via the intermediacy of a Diels-Alder adduct with the furan ring.
The reaction of simple dimethylallylamines with dimethyl acetylenedicarboxylate. Formation of 1-dimethylamino-2-allylmaleates via formal allyl transfer
Schwan, Adrian L.,Warkentin, John
, p. 1686 - 1694 (2007/10/02)
Tertiary amines bearing two methyl groups and an allylic substituent (X) raect 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.
