Functionalization of 9‐(Dicyanomethylene)fluorene Derivatives with Substituted Acetylenes

Abstract

Treatment of (2,7-dibromo-9H-fluoren-9-ylidene)malononitrile (1) with excesses of substituted acetylenes RCϵCH [R = Ph, MeC 6 H 4 , (η 5 -C 5 H 5 )Fe(η 5 -C 5 H 4 )] under Sonogashira coupling catalytic conditions afforded novel 9-[cyano(ethynyl)methylene]fluorene derivatives 2−4, respectively, in moderate yields. In these reactions, facile functionalization occurs at the 9-methylene position in the fluorene, one of the cyano groups being substituted by an acetylide moiety. In order to prepare the 2,7-diethynyl-substituted 9-(dicyanomethylene)-fluorene compounds 8−10, palladium-catalyzed coupling reactions between 2,7-dibromofluoren-9-one and RCϵCH in a

Synthesis and electro‐optical properties of polyfluorene modified with randomly distributed electron‐donor and rotaxane electron‐acceptor structural units in the main chain

“…2,7‐Dibromo‐9‐(dicyanomethylene) fluorene (3) was prepared through a condensation reaction between 2,7‐dibromofluoren‐9‐one with malononitrile at 110 °C in DMSO19–21 (see details and 1 H NMR spectrum in Supporting Information Fig. S2).…”

“…The incorporation of the nonrigid groups of electron‐donating triarylamine (TA), either as additional repeating units along macromolecular chains or as pendant groups, leads to better fluorescence efficiency and hole mobility in solid state 15–18. ITC studies of electron‐deficient fluorene derivatives, that is, 9‐dicyanomethylfluorene, proved the ability of this moieties to tune the band‐gaps and the electron‐transport properties 19–21…”

Antitumor activity of diethynylfluorene derivatives of gold(I)

“…33 Culture Collection. They were cultured in RPMI-1640 medium with 5% fetal bovine serum (complete cell culture medium) at 37°C in 5% CO 2 humidified incubator.…”

“…Organic model compounds 2 and 3 were obtained by the Sonogashira type coupling between 2,7-dibromofluorenes and the appropriate 1-alkyne in good yields. 33 The dicyano-substituted compound 4 was prepared from 3 by thermal reaction with malononitrile in DMSO. The digold(I) bis(acetylide) complexes were synthesized from the base-catalyzed dehydrohalogenation between Au(PPh 3 )Cl and 1 or 2,7-diethynylfluorene in the presence of NaOH in MeOH.…”

Carbon-rich organometallics: synthesis and characterization of new ferrocenyl end-capped bis(butadiynyl) fluorene derivatives

“…2-formyl-9-fluorenyl 1.354(6) Å [12], 2,7-diformyl-9-fluorenyl 1.340(3) Å [12], 2,7-diethynyl-9-fluorenyl 1.348 (3) Å [13]), trans-[Ph(Et 3 P) 2 PtC"CArC"CPt (PEt 3 ) 2 Ph] (Ar = 9-(ferrocenylmethylene)fluorene-2,7-diyl 1.37(2) Å [13], 9-(dicyanomethylene)fluorene-2,7-diyl 1.348(9) Å ) [14], 2,4,5,7-tetranitro-9-[cyano(dimethylamino)methylene]fluorene (1.388(4) Å ) [15], 2,7-dibromo-9-[cyano(ethynyl)methylene]fluorene derivatives (1.361 (8) and 1.363(7) Å ) [16] and other polynitrosubstituted 9-(dicyanomethylene)fluorenes [17]. There is a lengthening of the C(23)-C(26) bond (1.330(6) Å ) and shortening of the C(26)-C(27) bond (1.469(7) Å ), in line with the presence of p-conjugation along the fragment C(23)-C(26)-C(27) (see Fig.…”