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Phenol based aryliodonium salts were prepared by the reaction of [hydroxy(tosyloxy)iodo]arenes with aryl silyl ethers in the presence of trifluoromethanesulfonic acid. Structures of several aryliodonium salts with the hydroxy group in the para -position of the phenyl ring were established by single crystal X-ray crystallography. Under basic conditions, 4-hydroxyphenyl(phenyl)iodonium salts form a dimeric hypervalent iodine( iii ) complex, oxyphenyl(phenyl)iodonium ylidic salt, the solid structure of which was confirmed by X-ray crystallography. Phenolic iodonium salts are potentially useful phenol transfer reagents in reactions with various anionic nucleophiles.
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This content will become publicly available on October 16, 2026
Ferrocene-Templated Synthesis of Fused Aminofulvenes: Elaboration of Chalaniline A and a Reversed Regioisomer via a Ferroceno[b]chromone
Ferrocenes were studied as cyclopentadiene ring surrogates enroute to non-metallocene targets such as the aminofulveno[1,2-b]chromone natural product chalaniline A. Ferroceno[b]chromone, as an archetype of interest, was prepared from ferrocenecarboxylic acid (4 steps, 24% yield) via N,N-diethyl 2-iodoferrocenecarboxamide by Ullmann etherification with phenol followed by LDA-mediated anionic cyclization. Reactivity studies revealed that this planar chiral analogue of xanthone readily fragments into non-metallocene products upon reaction with electrophiles. 1-Methoxy-3-methylferroceno[b]chromone, prepared similarly by substituting O-methylorcinol for phenol, was advanced to chalaniline A and a transposed regioisomer by concomitant deferration and demethylation with AlCl3; formylation of the resulting cyclopentadiene-fused chromone with excess Vilsmeier reagent; and then Pinnick oxidation (NaClO2), methylation (TMSCHN2), and final transamination (PhNH2). Four compounds, including ferroceno[b]chromone and the C11/C12-transposed regioisomer of chalaniline A, were characterized by single crystal X-ray diffraction analysis.
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- Award ID(s):
- 2247031
- PAR ID:
- 10644530
- Publisher / Repository:
- Thieme
- Date Published:
- Journal Name:
- Synthesis
- Volume:
- 57
- Issue:
- 21
- ISSN:
- 0039-7881
- Page Range / eLocation ID:
- 3307 to 3314
- Subject(s) / Keyword(s):
- aminofulvenes demetallation directed ortho metallation heterocyclic ferrocenes planar chirality ring fused cyclopentadienes
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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