Preparation of Donor-σ-Acceptor Molecules Using Arene−Ruthenium Chemistry

Abstract

Several donor-sigma acceptor (D-sigma-A) molecules with thioalkyl side chains have been prepared by ruthenium-activated nucleophilic aromatic substition (S(N)Ar) reactions. Selective substitution of chloride from cyclopentadienyl(1,4-dichlorobenzene)ruthenium by using piperazine derivatives as nucleophiles is addressed. This selectivity, in combination with further manipulation of the complexes, allows the preparation of unsymmetrically functionalized tetraalkyl-p-phenylenediamine (TAPD) units which are difficult to synthesize by traditional organic S(N)Ar conditions. Phenanthroline-assisted decomplexation of the product arene-RuCp systems under UV irradiation is described.

Conical Gradient Junctions of Dendritic Viologen Arrays on Electrodes

“…The title compound was prepared in 82% yield from 10-bromo-1-decene by thiol-ene addition with thioacetic acid in the presence of 2,2′-azobis(isobutyronitrile) in toluene under reflux according to the procedure reported in the literature 34 . 1 H NMR (CDCl 3 , 25 °C) δ: 1.22–1.48 (br, CH 2 , 12H), 1.56 (quint, CH 2 , J = 7.3 Hz, 2H), 1.85 (quint, CH 2 , J = 7.2 Hz, 2H), 2.32 (s, SCOCH 3 , 3H), 2.86 (t, CH 2 , J = 7.3 Hz, 2H), 3.40 (t, CH 2 , J = 6.9 Hz, 2H).…”

Two-dimensional assembly and local redox-activity of molecular hybrid structures in an electrochemical environment

“…65 The required bifunctional hexyl chain with a bromine atom at one end and an acetyl-protected sulfur at the opposite end 7 has been synthesized from the bromohexene 6 and thioacetic acid in the presence of a radical source (yield 81%). 66 Bromohexene 6 has been converted to 7 in good yields (81%) by refluxing in toluene with thioacetic acid and 1,1 0 -azobis(cyclohexanecarbonitrile). The acetyl protected hexyl bromide 7 and the mono-hexylviologen derivative 4 have been heated to 110 1C in dimethylformamide (DMF) to form the acetyl-protected target structure 5 in very good yields (97%).…”

Amphiphilic liquid‐crystalline 4‐miktoarm star copolymers with a siloxane junction leading to cylindrically nanostructured templates for a siloxane‐based nanodot array

“…The preparation of the siloxane core with three PEO arms [(PEO) 3 ‐core‐(OH) 1 ] was performed according to the literature . A solution of (CHCH 2 ) 3 ‐core‐(OH) 1 (0.2 g, 0.47 mmol), PEO‐SH (1.77 g, 2.84 mmol), and AIBN (50 mg) in anhydrous toluene was degassed by three consecutive freeze–thaw–pump cycles and was then filled with argon gas.…”

“…A modified literature procedure was employed for this synthesis. 11 In a two-neck 100-mL flask equipped with a reflux condenser was added allyl-PEO (6.00 g, 10.2 mmol), thioacetic acid (3.88 g, 51 mmol), and AIBN (60 mg) in 30 mL of anhydrous toluene under an argon atmosphere. Degassing was performed by three consecutive freeze-pump-thaw cycles and then refilling with argon.…”

“…The preparation of the siloxane core with three PEO arms [(PEO) 3 -core-(OH) 1 ] was performed according to the literature. 11 A solution of (CH@CH 2 ) 3 -core-(OH) 1 (0.2 g, 0.47 mmol), PEO-SH (1.77 g, 2.84 mmol), and AIBN (50 mg) in anhydrous toluene was degassed by three consecutive freeze-thaw-pump cycles and was then filled with argon gas. The entire mixture was stirred at 60 8C for 18 h. After cooling to room temperature, the mixture was dissolved in 200 mL chloroform, washed with 1 N aqueous NaHCO 3 (3 times), brine, and water (3 times), and then dried over MgSO 4 .…”