ChemicalBook CAS DataBase List 3,4-Dithia-7H-cyclopenta[a]pentalene

3,4-Dithia-7H-cyclopenta[a]pentalene synthesis

14synthesis methods

Product Name:3,4-Dithia-7H-cyclopenta[a]pentalene
CAS Number:389-58-2
Molecular formula:C9H6S2
Molecular Weight:178.27

Cyclopentylthiophene can be used to synthesize donor-acceptor copolymers. It can be synthesized from 3,3'-Dibromo-2,2'-bithiophene and Bis[(pinacolato)boryl]Methane by copper-catalyzed ring-closure reaction.

25796-77-4 Synthesis

4H-Cyclopenta[2,1-b:3,4-b']dithiophen-4-one

25796-77-4
159 suppliers
$22.00/100mg

389-58-2
196 suppliers
$24.00/100mg

Yield:389-58-2 66%

Reaction Conditions:

with potassium hydroxide;hydrazine in ethylene glycol at 190; for 13 h;

Steps:

1

After placing compound (77) (96 mg, 0.499 mmol), hydrazine monohydrate (268 mg, 5.35 mmol), potassium hydroxide (294 mg, 5.249 mmol) and ethylene glycol (5 mL) in a heat-dried stoppered test tube, the mixture was slowly heated from room temperature to 190°C and then refluxed at 190°C for 13 hours. After then cooling the mixture to room temperature, water was added and the organic phase was extracted with ether. The organic phase was washed with water and brine and dried over magnesium sulfate, and concentrated under reduced pressure. It was then purified by silica gel column chromatography (hexane:ethyl acetate = 10:1) to obtain the target compound K (59 mg, 66% yield) as a white solid. The analysis results and chemical formula for the obtained compound K are shown below. Upon measuring the obtained compound K by CV, the oxidation potential was 0.68 V and the reduction potential was -2.88 V. The peak wavelength in the absorption spectrum of compound K was 310 nm. TLC R_f = 0.7 (hexane: CH₂Cl₂ = 2 :1): ¹H NMR (270 MHz, CDCl₃): δ 7.17 (d, 2H, J = 4.8 Hz), 7.09 (d, 2H, J = 4.8 Hz), 3.54 (s, 2H): GC-MS (EI): m/z = 178 (M⁺).

References:

EP1997821,2008,A1 Location in patent:Page/Page column 32