66650-34-8Relevant academic research and scientific papers
JANUS-TYPE ISOPROPYL GROUPS REVEALED BY 1H-NMR SPECTRA OF ALKYLPYRIDINES WITH LANTHANIDE SHIFT REAGENTS (LSR)
Uncuta, Cornelia,Balaban, Teodor-Silviu,Gheorghiu, Mircea D.,Stanescu, Ligia,Petride, Aurica,Balaban, Alexandru T.
, p. 4673 - 4676 (1985)
Two isomeric pyridines were designed and prepared : 2-isopropyl-4,5,6-trimethyl- (3) and 2-isopropyl-3,4,6-trimethyl-pyridine (7) ; the latter, with a buttressed isopropyl, leads to much lower induced shifts by Eu(dpm)3 and Pr(dpm)3 than the former, owing to the conformation in which the Janus-type iPr group shows to the LSR a t-butyl-like face.
Acylations des cetones α-β-ethyleniques catalysees par les acides sulfoniques : synthese concomitante de sels de pyrylium et de dihydro-2,3-pyrones-4
Graindorge, Herve,Roussel, Christian
, p. 454 - 458 (2007/10/02)
The acylation of α,β-ethylenic ketones by carboxylic acid anhydrides catalyzed by sulfonic acids lead to the expected unsymmetrical pyrylium salts. 2,3-Dihydro-pyran-4-ones are also formed.The respective yields depend upon the alkyl substituents of the starting material.
