Table 3. Control Experiments for the Vitamin B₁₂-Catalyzed Addition/1,2-Phenyl Migration^a.

entry	deviation from the reaction conditions	yield of3a[%]b
1	-	80
2	no B12	0
3	no Zn	0
4	no light	0
5	no B12, Zn and light	0
6	under air	7
7	no surfactant	31
8	no butan-1-ol	65

^aOptimized reaction conditions: diethyl 2-phenyl-2-vinylmalonate (1, 0.10 mmol), 1-bromododecane (3 equiv, 0.30 mmol), vitamin B₁₂ (2.5 mol %), Zn (3 equiv), DTAC (0.35 mmol), n-BuOH (1.25 mmol), H₂O (5 mL), green LEDs (525 nm), 16 h, 40 °C.

^bYields determined by GC analysis with mesitylene as an internal standard.