Table 1 Exploration of optimal conditions for one-pot tandem DKR catalysis with Pd@C-Cage-CALB catalyst, and the comparison of catalytic activities of different catalysts^a


Entry	Catalyst	Time (h)	Yield (%)^b	e.e. (%)	Specific activity (U/mg)^e
1	Pd@C-Cage-CALB	0.5	47.15	99	2.40
2	Pd@C-Cage-CALB	1	61.66	99	-
3	Pd@C-Cage-CALB	2	95.35	99	-
4	Pd@C-Cage-CALB	2.5	>99	99	-
5	Pd/C + Novozym 435	2.5	9.02	99	0.24
6	Physical mixture of Pd@C-Cage⁺ + CALB^c	2.5	37.69	99	0.92
7	Physical mixture of Pd@C-Cage⁺ + C-Cage-CALB^d	2.5	48.49	99	1.25
8	Pd₁/C-Cage-CALB	2.5	31.07	99	0.87
9	Pd₂/C-Cage-CALB	2.5	28.27	99	0.89
10	Pd/CALB	2.5	2.41	99	0.11

^aReaction conditions: 0.2 mmol of A, 0.5 mmol of B, 3 mg of Catalyst (1.31 mg of CALB) 60 °C, 1 atm H₂, and 3 mL of toluene.
^bReaction products were analyzed and identified by LC and ¹H NMR.
^{c, d}The counteranion for Pd@C-Cage⁺ is Cl⁻.
^e \({{{\rm{Specific\; Activity}}}}=\frac{{\Delta n}_{{product}}}{{\Delta {t}\times m}_{{CALB}}}{\Delta n}_{{product}}\) represents the mole amount of product generated within 30 minutes. \(\Delta t\) represents the time required for the reaction to proceed at a linear rate, which in this reaction is 30 minutes. \({m}_{{CALB}}\) represents the mass of CALB. Here, 1 U is defined as the amount of CALB required to catalyze the conversion of 1 μmol of substrate per minute under the specified conditions.

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