6500-64-7Relevant articles and documents
ACYL HYDRAZONE LINKERS, METHODS AND USES THEREOF
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Paragraph 00238, (2019/07/04)
The present application is directed to compounds of Formula (I)-(VI): (I), (II), (III), (IV), (V) (VI), (VII) and (VIII), compositions comprising these compounds and their uses, for example as medicaments and/or diagnostics.
Hydrogen Bonded Phenol-Quinolines with Highly Controlled Proton-Transfer Coordinate
Parada, Giovanny A.,Glover, Starla D.,Orthaber, Andreas,Hammarstr?m, Leif,Ott, Sascha
, p. 3365 - 3372 (2016/07/23)
A series of polycyclic phenols with intramolecular hydrogen bonds (IMHB) to quinolines was synthesized by Friedl?nder annulation of cycloalkanone-functionalized anisoles with 2-aminobenzaldehyde. The prepared compounds represent the first series of IMHB phenols in which the substitution and conjugation patterns between the phenols and the hydrogen bond acceptors are kept constant, and in which comparable electronic interaction between the two subunits is thus ensured. The distance and relative orientation between the phenolic OH and the quinolone nitrogen atom is controlled by 1,3-cycloalkadienes of different ring sizes to which the phenol and quinoline subunits are formally annulated.1H δ(OH) chemical shift and X-ray crystal structure characterization support the conclusion that the size and conformational preference of the 1,3-cycloalkadiene rings control the H-bond geometry and strength. As a result, the oxygen to nitrogen distances differ by as much as 0.30 ? across the series.
A photo-favorskii ring contraction reaction: The effect of ring size
Kammath, Viju Balachandran,?olomek, Tomá?,Ngoy, Bokolombe Pitchou,Heger, Dominik,Klán, Petr,Rubina, Marina,Givens, Richard S.
, p. 1718 - 1729 (2013/03/29)
The effect of ring size on the photo-Favorskii induced ring-contraction reaction of the hydroxybenzocycloalkanonyl acetate and mesylate esters (7a-d, 8a-c) has provided new insight into the mechanism of the rearrangement. By monotonically decreasing the ring size in these cyclic derivatives, the increasing ring strain imposed on the formation of the elusive bicyclic spirocyclopropanone 20 results in a divergence away from rearrangement and toward solvolysis. Cycloalkanones of seven or eight carbons undergo a highly efficient photo-Favorskii rearrangement with ring contraction paralleling the photochemistry of p-hydroxyphenacyl esters. In contrast, the five-carbon ring does not rearrange but is diverted to the photosolvolysis channel avoiding the increased strain energy that would accompany the formation of the spirobicyclic ketone, the "Favorskii intermediate 20". The six-carbon analogue demonstrates the bifurcation in reaction channels, yielding a solvent-sensitive mixture of both. Employing a combination of time-resolved absorption measurements, quantum yield determinations, isotopic labeling, and solvent variation studies coupled with theoretical treatment, a more comprehensive mechanistic description of the rearrangement has emerged.
