“A Jack of Trio”-robust one-pot metal free oxidative amination, azidation and peroxidation of phenols

Abstract

Facile generation of quaternary carbon centres has been realised in the presence of phenyl trimethyl ammonium tribromide (PTAB) mediated oxidative dearomatisation.

Copper‐Catalyzed Oxidative Dearomatization of 2‐Naphthols via Etherification

“…1‐Hexyl‐1‐((1‐hexylnaphthalen‐2‐yl)oxy)naphthalen‐2(1 H )‐one ( 3c ) was prepared (purified by column chromatography, eluent: V (PE)/ V (Acetone) = 30/1) as a yellow oil (86.3 mg, 95% yield). 1 H NMR (400 MHz, CDCl 3 ) δ : 7.97 (d, J = 8.4 Hz, 1H), 7.58 (d, J = 8.0 Hz, 1H), 7.50 (d, J = 10.0 Hz, 1H), 7.43—7.38 (m, 3H), 7.30—7.21 (m, 4H), 6.30 (d, J = 9.6 Hz, 1H), 5.99 (d, J = 9.2 Hz, 1H), 3.36—3.20 (m, 2H), 2.16—2.00 (m, 2H), 1.93—1.72 (m, 2H), 1.64—1.57 (m, 2H), 1.53—1.34 (m, 6H), 1.30—1.20 (m, 6H), 0.94 (t, J = 7.2 Hz, 3H), 0.85 (t, J = 6.8 Hz, 3H).…”

“…Subsequently, Uchida and coworkers reported Fe(Salan) complex catalyzed intramolecular oxidative dearomatization [8b]. In 2017, Sarkar and coworkers disclosed a PTAB mediated oxidative dearomatization reaction of naphthols, while only homo‐etherification was reported (Scheme a). To date, the oxidative dearomatization reaction of two different naphthol substrates via cross etherification remains great challenge given the selectivity issues.…”

Visible Light Assisted Selenylative Intramolecular Dearomative Carbo‐Spirocyclisation (IDCS) of Homologated‐Ynones

“…Common procedures include metal and hypervalent iodine mediated oxidation, transition metal‐catalyzed allylations, chiral anion driven fluorination and organo‐catalytic approaches . Of late, our group explicated the usefulness of the tri‐bromides in these approaches . Recently, the emerging Catalytic Asymmetric Dearomatization (CADA) reported by You has been an attractive one.…”

Visible‐Light‐Promoted Intermolecular Oxidative Dearomatization of β‐Naphthols with N‐Hydroxycarbamates

“…[2] Of particular note, oxidative dearomatization reactions have emerged as attractive methods given their atom-economic nature and useful products generated therein. [1d,g,h,m,o,p,r] Accordingly,t remendous efforts have been made on the oxidative dearomatization of phenolsa nd naphthols.I ng eneral, these reported methods are mediated by hypervalent iodine reagents, [3] transition metals [4] and others, [5] and the requirement of strongo xidants or harsh conditions presentsachallenge fors ubstrate scope and practical application.M eanwhile, the past decadeh as witnessed ar enaissance of visible-light-mediated photoredox catalysis since it produces open-shell species under mild conditions to promotev aluable transformations with ag ood tolerance of functional groups. [6] Despite this blooming of photo-chemistry,t he utilization of visible-light-mediated photoredox catalysis in intermoleculard earomatization of naphthols remainsl argely underexplored.…”

“…> 20:1) [Scheme 4 (1)]. Finally,the rearrangement of CÀOc oupling product (3a)t oC ÀNc oupling compound (5) occurred in the presence of Cs 2 CO 3 ,w hichw as followed by subsequentr eductioni nt he presence of Mo(CO) 6 [12] to deliver product 6 in 68 %y ield over two steps [Scheme 4 (2)]. T his transformation simultaneously provides an attractive and syntheticallyu seful approach to access the aminatived earomatization product.…”