Exclusively explored electrochemical halogenation of aryl compounds; periodical updates: Since 2000

Linear Paired Electrolysis—Realising 200 % Current Efficiency for Stoichiometric Transformations—The Electrochemical Bromination of Alkenes

“…Accordingly, when 1,3-dimethoxybenzene ( 8) was electrolysed under the conditions of the linear paired electrolysis the desired product 9 was obtained in 94 % yield utilising 1.2 F, which results in a current efficiency of 168 % (Scheme 8). [14] In conclusion, we have optimised a linear paired electrolysis for the dibromination of alkenes in up to 100 % yield and a perfect current efficiency of 200 %. Several important reaction parameters were identified, optimised, and a functional group tolerance test identified other starting materials which can be applied in the linear paired bromination, such as electron-rich arenes.…”

Lineare gepaarte Elektrolyse – Realisierung von 200 % Stromausbeute in stöchiometrischen Umsetzungen – die elektrochemische Bromierung von Alkenen

“…Die Elektrolyse ergab das gewünschte Produkt 9 in 94 % Ausbeute und einer Stromausbeute von 168 %, nachdem eine Strommenge von 1.2 F appliziert wurde (Schema 8). [14] Zusammenfassend lässt sich konstatieren, dass die lineare gepaarte Elektrolyse zur Bromierung von Alkenen in bis zu 100 % Ausbeute und einer perfekten Stromausbeute von 200 % realisiert werden konnte. Einige wichtige Reaktionsparameter wurden identifiziert und optimiert, und ein Functional-Group-Tolerance-Test zeigte weitere Edukte, die in der linearen gepaarten Bromierung einsetzbar waren, wie etwa Elektronen-reiche Aromaten.…”

Electrochemical Selective Mono‐ and Polychlorination of Substituted Thiophenes

“…Although the monochlorination of thiophenes is well documented, [17] the highly efficient methods for selective dichlorination or trichlorination of thiophenes remain underdeveloped [18] . The dichlorination or trichlorination methods require excess toxic or corrosive chlorinating reagents, but it results in poor atom economy and serious environmental contamination that limits its applicability from the viewpoint of green chemistry [9c,19] . Recently, synthetic electrochemistry has served as an advantageous technology over the conventional method because of its greenness and sustainability [20] .…”

“…Recently, synthetic electrochemistry has served as an advantageous technology over the conventional method because of its greenness and sustainability [20] . In 2000, Anbu Kulandainathan and co‐workers reported an electrochlorination of p‐xylene using precious metal oxide coated over titanium (Titanium Substrate Insoluble Anode‐TSIA), which gave 68 % 2‐chloro‐p‐xylene product, but difficult to selectively obtain polychlorinated products on demand, only producing 2 % 1,4‐dichloro‐2,5‐dimethylbenzene (Scheme 2B) [9c,19] . In our continuing interest in the electrochemical preparation of functional thiophene compounds, [21] herein we report a highly selective electrochemical chlorination protocol to realize monochlorination, dichlorination and trichlorination of thiophenes (Scheme 2C).…”