4.2.2. 2-[Carboxy(phenyl)methyl]benzoic Acid (**10b**)

Prepared according to the general procedure GP1 from 3-phenyl-2,3-dihydro-1*H*inden-1-one [16]. Yield 2.017 g, 82%. Colorless amorphous solid. 1H NMR (400 MHz, DMSO-*d*6) *δ* 12.81 (s, 2H), 7.95–7.82 (m, 1H), 7.53–7.44 (m, 1H), 7.41–7.32 (m, 3H), 7.32–7.22 (m, 3H), 7.13–7.04 (m, 1H), 5.97 (s, 1H). 13C NMR (101 MHz, DMSO-*d*6) *δ* 173.9, 169.1, 140.6, 139.5, 132.1, 131.1, 130.7, 130.3, 129.5, 129.0, 127.4, 127.3, 53.6. HRMS (ESI/Q-TOF) *m*/*z*: [M + Na+] <sup>+</sup> Calcd for C15H12O4Na<sup>+</sup> 279.0628; Found 279.0623.
