ChemInform Abstract: Synthesis of peri‐Hydroxynaphthaldehydes.

Abstract

ChemInform Abstract The title compounds (I), (III), (VI) and (VII) are prepared by a novel procedure in improved yields. These compounds are of interest as synthons for the preparation of peri-anellated heterocyclic systems.

Natural product based inhibitors of the thioredoxin–thioredoxin reductase system

“…O-Demethylation of S1 and S9 under a variety of conditions led to extensive decomposition, and therefore we had to devise an alternative route to access the desired free phenols (Scheme 3). MOM-protection of 6 23 was followed by substitution with 4-fluoro-1-naphthalenecarboxaldehyde 24 or the fluoride 4 in the presence of Barton's base 18 to give the diaryl ethers 8a and 8b, respectively. Dakin reactions, reductive deformylations, and oxidative spirocyclizations provided the MOM ethers 10a and 10b, which were subsequently deprotected with TMS-Br 25 in good yields to give the desired S11 and S12.…”

Naphthaldehydes

“…However, the latter reaction is accompanied by the formation of impurities, which are difficult to separate. 42…”

“…44 The Vilsmeier reaction of 1,5-dimethoxynaphthalene afforded 4,8-dimethoxy-1-naphthaldehyde (37) with a small impurity of dialdehyde 38. 56 It was demonstrated 42 that the latter can also be synthesised by Rieche formylation of monoaldehyde 37 (93% yield).…”

Structure of 4,8-dihydroxynaphthalene-1,5-dicarbaldehyde by the data of 1H NMR Spectroscopy. Spin-spin coupling through a hydrogen bond

“…In this study we report on some features of the fine structure of 4,8-dihydroxynaphthalene-1,5-dicarbaldehyde (I) [1] recently synthesized in our laboratory, a compound promising for versatile synthetic purposes.…”

“…The analysis of 1 symmetric dialdehyde I and cyclic hemiacetal II in a ratio ~55 : 45. By treating the mixture with alcohol we isolated the "fi xed" hemiacetal form III of the cyclic tautomer II.…”