Journal of Chemistry / 2020 / Article / Tab 2

Research Article

Synthesis of Phenols via Metal-Free Hydroxylation of Aryl Boronic Acids with Aqueous TBHP

Table 2

Optimization of hydroxylation parametersa.

EntryOxidant (equiv.)Base (equiv.)Temp. (°C)Time (h)Yield (%)b,c

1TBHP (1)Cs2CO3 (1)70347
2TBHP (2)Cs2CO3 (1)70550d
3TBHP (2)K2CO3 (0.5)60525
4TBHP (2)K2CO3 (1)25510
5TBHP (2)Pyridine (1)6010NR
6TBHP (2)Et3N (1)605NR
7TBHP (2)Et2NH (1)60522
8TBHP (2)NaOH (1)50576
9TBHP (2)NaOH (1)25545
10TBHP (2)NaOH (1)80260
11NaOH (1)505NR
12TBHP (2)505Traces
13TBHP (2)KOH (1)50580
14TBHP (2)KOtBu (1)50592(87)e

aReaction conditions: phenylboronic acid (1 mmol), aqueous TBHP base, and water (1 mL) stirred at designated temperature and time; bIsolated yield after workup; cProducts were characterized by MP, FTIR, and 1H- and 13C-NMR; dTHF was added to mix reactants. eYield after 2 hours.

We are committed to sharing findings related to COVID-19 as quickly as possible. We will be providing unlimited waivers of publication charges for accepted research articles as well as case reports and case series related to COVID-19. Review articles are excluded from this waiver policy. Sign up here as a reviewer to help fast-track new submissions.