Electrolytic Partial Fluorination of Organic Compounds. 32.¹ Regioselective Anodic Mono- and Difluorination of Flavones

Synthesis of fluorinated oxygen- and sulfur-containing heteroaromatics

“…Hou et al carried out a number of anodic fluorination experiments on several flavones [72]. Using a platinum electrode in anhydrous acetonitrile with Et 3 N.3HF as the supporting electrolyte, substrates 109a-c were transformed to their fluorinated derivatives 110a-c in yields ranging from 19% to 62% (Table 9).…”

Unique solvent effects on selective electrochemical fluorination of organic compounds

“…On the other hand, anodic fluorination of b-lactams having an a-phenylthio group and a flavone derivative as shown in Schemes 3 and 4 proceeds quite well even without pulse electrolysis because passivation does not take place [20,21].…”

Electrolytic fluorination of organic compounds

“…In Et 3 N·3HF, it afforded 3-fluoroflavone (167), but using Et 4 NF·4HF led to formation of 2,3-difluoro-2,3-dihydroflavone (168) (Scheme 54). 98,99 Highly regioselective electrolytic direct fluorination at the a-position to the ring-oxygen atom of the chroman-4-one derivatives 169a -c was successfully performed using Et 4 NF·4HF/DME to give the corresponding 2-fluorochromanones 171a-c. 100,101 The compound 171b could also be obtained stereoselectively from an alternative electrofluorination of the homoisoflavone derivative 170, as shown in Scheme 55. 100, 101 2.1.14.4.…”

“…Organoantimony compounds. Electrofluorination of triphenylantimony(98) was conducted in the presence of the Et 3 N·3HF/MeCN system to give triphenylantimony difluoride(99) in excellent yield (Scheme 31) 75. 2.1.11.…”