Ethyl α‐(Triphenylphosphoranylidene)amino‐β‐ferrocenylacrylate as a Starting Material for [2+2] Cycloadditions, Including the Aza‐Wittig Reaction

Abstract

Ethyl α-(triphenylphosphoranylidene)amino-β-ferrocenylacrylate, synthesized from the corresponding azide, was treated with a few selected electrophilic agents potentially capable of undergoing the aza-Wittig reaction. The transformations with aroyl chlorides and phenylisocyanate afforded a series of novel 4-(ferrocenyl)methylidene-2-aryloxazolones. On treatment of the phosphorimino compound with DMAD two competitive reactions took place on the C=C and N=P bonds, giving rise to a novel amino(ferrocenyl)butadiene and a ferrocenyl-substituted aza-pentadienylphosphory-

Synthesis, IR-, NMR-, DFT and X-ray study of ferrocenyl heterocycles from thiosemicarbazones. Part 21: Study on ferrocenes

“…These reactions afforded complex mixtures of methylthio-substituted products in comparable yields including imidazolones and pyrimidones (7, 9a,b and 8a,b). From the reaction mixture of 5a 3-ferrocenyl-4-[(E)-1,2-bis(methoxycarbonyl)vinyl]-5-methylthio [1,2,4]triazole (6) could also be isolated as the result of oxidative cyclization associated with conjugate addition on DMAD. A chelate-stabilized enaminoester (10) was obtained as an additional product in a considerable yield (32%) from the reaction of 5b.…”

“…Besides these applications the sandwich complexes have also been shown different biological activities and were also used in therapy [2]. Earlier our group have synthesized and characterized different ferrocene-containing heterocycles of potential and -in a few cases [3e] -proved biological activity, including ferrocenyl-pyrazoles-and pyrazolines-, condensed 1,2,4-triazoles-[3], imidazoles- [4], diazepines- [5], oxazoles- [6] and pyridazines [7]. According to the literature different heterocyclic compounds possess valuable pharmaceutic properties including anticancer effects [8][9][10][11].…”

Synthesis and structure of planar chiral ferroceno[d]pyridazinones, the first representatives of a novel class of fused metallocenes

“…Optical rotations were measured with a Zeiss Polamat A polarimeter. The 1 H and 13 C NMR spectra were recorded in DMSO-d 6 or CDCl 3 solution in 5 mm tubes at RT, on a Bruker DRX-500 spectrometer at 500 ( 1 H), 125 ( 13 C) and 50 ( 15 N) MHz, with the deuterium signal of the solvent as the lock and TMS as internal standard ( 1 H, 13 C) and NH 3 (liq) as external reference ( 15 N). The 15 N NMR chemical shifts were obtained and assigned from the 1 He 15 N HMBC spectra.…”

“…Besides these applications the sandwich complexes have also been shown different biological activities and were also used in therapy [2]. Earlier, our group have synthesized and characterized different ferrocene-containing heterocycles of potential and e in a few cases [3e] -proved biological activity, including ferrocenyl-pyrazolesand pyrazolines-, condensed 1,2,4-triazoles-[3], imidazoles- [4], diazepines- [5], oxazoles- [6], dihydropyrimidines [7], quinolines [8] and pyridazines [9]. On the other hand, according to the literature a wide variety of heterocyclic scaffolds possess valuable pharmaceutic properties including anticancer effects [10], however much less attention has been paid to the chemistry of ferrocenocondensed heterocycles offering the possibility to introduce planar chirality into the molecule [11].…”

Synthesis of Ferrocene Tethered Heteroaromatic Compounds Using Solid Supported Reaction Method, their Cytotoxic Evaluation and Fluorescence Behavior.

“…Investigation on ferrocene substituted tamoxifen and ferrocenyl chloroquine derivatives are among the many examples where systematic functionalization of ferrocene have improved the activity of the drug.A range of different ferrocene linked heterocyles like ferrocenyl‐2‐thiazolamine, ferrocenyl‐2‐oxazolines, quinolines, indoles, triazoles, imidazoles, dihydropyrimidines etc. have been reported recently by several groups and their study confirmed remarkable potential in significant biological properties ranging from microbial inhibition, anti‐HIV, cytotoxicity to anti‐inflammatory activities …”