Table 1 Reaction optimization.

Reaction conditions: 1a (0.20 mmol), 2 (0.30 mmol), base (3.0 equiv), solvent (1.0 ml), 24 hours, under Ar. CCDC, Cambridge Crystallographic Data Centre.

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1X[Rh] (mol %)BaseSolventT (°C)Yield (%)*
1Br (2a)Rh(PPh3)3Cl (6.0)Cs2CO3Toluene11010
2Br (2a)Rh(PPh3)3Cl (6.0)tBuONaToluene11033
3Br (2a)Rh(PPh3)3Cl (6.0)tBuOLiToluene11084
4Br (2a)Rh(PPh3)3Cl (6.0)tBuOLiPhCl11089
5Br (2a)Rh(PPh3)3Cl (6.0)tBuOLiPhCF311091
6Br (2a)Rh(PPh3)3Cl (6.0)tBuOLim-Xylene11094
7Br (2a)Rh(PPh3)3Cl (6.0)tBuOLim-Xylene8096
8Br (2a)Rh(PPh3)3Cl (6.0)tBuOLim-Xylene6015
9Cl (2a′)Rh(PPh3)3Cl (6.0)tBuOLim-Xylene11084
10I (2a″)Rh(PPh3)3Cl (6.0)tBuOLim-Xylene110Trace
11Br (2a)Rh(PPh3)3Cl (3.0)tBuOLim-Xylene8081
12Br (2a)Rh(PPh3)3Cl (1.0)tBuOLim-Xylene8064
13Br (2a)[Rh(cod)Cl]2 (3.0)tBuOLim-Xylene8011
14Br (2a)[Rh(cod)Cl]2 (3.0)tBuOLim-Xylene8064
15Br (2a)tBuOLim-Xylene800

*Isolated yields.

†With 10 mol % PPh3.