fig2
![Direct construction of <i>d</i><sub><i>3</i></sub>-methylated all-carbon quaternary stereocenters through carbene-catalyzed desymmetrization](https://image.oaes.cc/9f92960f-7fc6-4047-94c0-f6600db554e5/CS-2023-4.fig.2.jpg)
Figure 2. Optimized conditions[a]. [a] Standard condition: 1a (0.1 mmol), 2a (1.2 equiv), NHC.HX (10 mol%), solvent (0.1 M), 30 °C, and 24 h, then SiO2, 70 °C, and 10 h; [b] Yield of the product 3a after column chromatography; [c] Determined via 1H NMR spectroscopy; [d] Determined by chiral HPLC, % ee = (R-S) / (R + S) * 100.