531-59-9Relevant articles and documents
Applied photochemistry - Light controlled perfume release
Derrer, Samuel,Flachsmann, Felix,Plessis, Caroline,Stang, Melanie
, p. 665 - 669 (2007)
Ambient light is one of the most suitable available trigger conditions for the release of covalently bound volatile odorants in home- and laundry-care applications. We report on three complementary classes of light-cleavable fragrance precursors, covering the controlled release of odorants with a wide range of functional groups. o-Hydroxy cinnamates 1 undergo a UV-induced double bond isomerization followed by transesterification to release coumarin and a fragrance alcohol of choice. α-Alkoxyacetophenones 10 and α,α-dialkoxyacetophenones 12 undergo Norrish type II fragmentations upon UV-irradiation, thereby releasing one or two equivalents of fragrant aldehydes, respectively. Finally, photoexcited Xanthenoic esters 22 undergo fragmentation to release reactive acyl radicals, which further cyclize onto internal olefins to form perfumery lactones of various ring sizes. Schweizerische Chemische Gesellschaft.
ACCUMULATION OF COUMARINS IN ELICITOR-TREATED CELL SUSPENSION CULTURES OF AMMI MAJUS
Hamerski, Daria,Beier, Ross C.,Kneusel, Richard E.,Matern, Ulrich,Himmelspach, Karl
, p. 1137 - 1142 (1990)
Heterotrophic cell suspension cultures were initiated from hypocotyls of young Ammi majus L. seedlings.When these cultures were propagated continuously in the dark, they produced only traces of the coumarin umbelliferone.Upon addition of fungal cell wall fractions, i.e. a skleroglucan or an elicitor from either Phytophthora megasperma f. sp. glycinea or Alternaria carthami, the cells excreted large amounts of umbelliferone in addition to isopimpinellin, (S)-marmesin, (R)-ammirin, umbelliferone--ether and umbelliferone--ether.The last two compounds are new compounds and appear to be derived from 7-O-prenylumbelliferone, a coumarin that has been identified in from other plants.The Phytophthora-elicitor was the most effective inducer of coumarin accumulation.When cultures which had been elicited for 3 hr were pulsed with L-14C>phenylalanine for 7 hr, all the coumarins and an additional, still unidentified compound in the extracts were labelled efficiently.Our results suggest that A. majus cells are particularly suitable for biosynthetic studies on various coumarins as well as for regulatory studies of the inhibition of coumarin phytoalexin accumulation.
Cu-Catalyzed Phenol O-Methylation with Methylboronic Acid
Bartlett, Mairead E.,Chavez, Angela K.,Gaffney, Uma Bhagwat,Gorin, David J.,Lee, Joyce,Sharew, Betemariam,Wu, Miranda,Zhu, Yingchuan
supporting information, p. 5661 - 5664 (2021/11/11)
A Cu-catalyzed oxidative cross-coupling of phenols with methylboronic acid to form aryl methyl ethers has been developed, expanding the scope of Chan-Evans-Lam alkylation. Electron-deficient phenol derivatives with a broad array of functional groups are methylated in high yields. Increased reaction temperature and catalyst loading enables the methylation of substrates incorporating pyridine and dihydroquinolone motifs. Electron-rich phenol derivatives are poor substrates for the methylation; the characterization of C?H homodimerization products formed from these substrates illuminates a competing mechanistic pathway.
Trialkylammonium salt degradation: Implications for methylation and cross-coupling
Assante, Michele,Baillie, Sharon E.,Juba, Vanessa,Leach, Andrew G.,McKinney, David,Reid, Marc,Washington, Jack B.,Yan, Chunhui
, p. 6949 - 6963 (2021/06/02)
Trialkylammonium (most notably N,N,N-trimethylanilinium) salts are known to display dual reactivity through both the aryl group and the N-methyl groups. These salts have thus been widely applied in cross-coupling, aryl etherification, fluorine radiolabelling, phase-transfer catalysis, supramolecular recognition, polymer design, and (more recently) methylation. However, their application as electrophilic methylating reagents remains somewhat underexplored, and an understanding of their arylation versus methylation reactivities is lacking. This study presents a mechanistic degradation analysis of N,N,N-trimethylanilinium salts and highlights the implications for synthetic applications of this important class of salts. Kinetic degradation studies, in both solid and solution phases, have delivered insights into the physical and chemical parameters affecting anilinium salt stability. 1H NMR kinetic analysis of salt degradation has evidenced thermal degradation to methyl iodide and the parent aniline, consistent with a closed-shell SN2-centred degradative pathway, and methyl iodide being the key reactive species in applied methylation procedures. Furthermore, the effect of halide and non-nucleophilic counterions on salt degradation has been investigated, along with deuterium isotope and solvent effects. New mechanistic insights have enabled the investigation of the use of trimethylanilinium salts in O-methylation and in improved cross-coupling strategies. Finally, detailed computational studies have helped highlight limitations in the current state-of-the-art of solvation modelling of reaction in which the bulk medium undergoes experimentally observable changes over the reaction timecourse. This journal is
