14002-97-2Relevant articles and documents
Xanthan sulfuric acid: An efficient and recyclable solid acid catalyst for Pechmann condensation
Kuarm, B. Suresh,Madhav, J. Venu,Rajitha
, p. 1770 - 1777 (2012)
In this report, substituted coumarins are formed via Pechmann condensation using various substituted phenols and ethyl acetoacetates in the presence of xanthan sulfuric acid as a solid acid catalyst under solvent-free conditions. This method is very simple, costeffective, and has shorter reaction times, and the catalyst could be reused. Copyright Taylor & Francis Group, LLC.
Synthes?s and character?zat?on of new tr?azole and coumar?n-derived heterocycl?c compounds part I
Gümrük?üo?lu, Nurhan,Imran, Muhammad,Iqbal, Inam
, p. 1097 - 1106 (2020/01/09)
Synthesis of ethyl ester of acetic acid containing 5-oxo-[1,2,4] triazole ring (2) was achieved by the condensation of 3-substituted-4-amino-1H-1,2,4-triazol-5(4H)-one (1) with ethyl bromoacetate in basic medium. Compound 2, was then further reacted with hydrazine hydrate to form acid hydrazide, which is 2-(4-amino-3-substituted-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)acetohydrazide (3). Compound 3 was later treated with three different diverse coumarin aldehydes (6, 12, 18) resulted in the formation of arylidene hydrazides as cis–trans conformers (7, 8, 13, 14, 19, 20). In conclusion, we synthesized 1,2,4-triazole Schiff bases derived from the condensation of 3-substituted-4-amino-1,2,4-triazole-5-on and formylhydroxy-4-methylcoumarin derivatives, which have been characterized by, spectroscopic measurements (IR, 1H-NMR, 13C-NMR and elemental analysis).
13C Nuclear Magnetic Resonance Spectroscopy of 4-Methylcoumarins (4- Methyl-2H-1-benzopyran-2-ones)
Parmar, V. S.,Singh, S.,Boll, P. M.
, p. 430 - 433 (2007/10/02)
The 13C NMR spectra of 36 differently substituted 4-methylcoumarins (4-methyl-2H-1-benzopyran-2-ones) have been recorded.The effects of an alkyl side-chain at C-3 on the chemical shift values and that of a methoxy or an acetoxy group in place of a hydroxy group have been observed and rationalized.This study may be helpful in the structure elucidation of nei and natural 4-methylcoumarins. KEY WORDS 13C NMR chemical shifts 4-Methylcoumarins 4-Methyl-2H-1-benzopyran-2-ones.