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. Author manuscript; available in PMC: 2008 Nov 21.
Published in final edited form as: J Am Chem Soc. 2006 May 10;128(18):6054–6055. doi: 10.1021/ja061105q

Table 2.

Synthesis of piperazinone 9a

Entry Pd source
(mol%)		 Ligand
(mol%)		 Additive
(mol%)		 Temp.
(°C)		 Yield
(%)b 		ee
(%)c
1 [Pd(C3H5)Cl]2(2) (R,R)- 4 (6) none rt trace NA
2 [Pd(C3H5)Cl]2(2) (R,R)- 4 (6) Cs2CO3 (100) rt 0 NA
3 [Pd(C3H5)Cl]2(5) (R,R)- 4 (15) HOAc (10) rt traced NA
4 Pd2(dba)3CHCl3(5) (R,R)- 4 (15) HOAc (10) rt 51 NA
5 Pd2(dba)3CHCl3(5) (R,R)- 4 (15) BSA (100) rt 50 NA
6 Pd2(dba)3CHCl3(5) (R,R)- 4 (15) HOAc (10) 0 to rt 65e 89
7 Pd2(dba)3CHCl3(5) rac- 4 (15) HOAc (10) rt 88e NA
8 Pd2(dba)3CHCl3(5) (R,R)- 4 (15) HOAc (10) 0 to rt 80e,f 96
9 Pd2(dba)3CHCl3(5) (R,R)- 4 (15) HOAc (10) 0 to rt 82e,g 97.5
a

Unless otherwise indicated, all reaction were performed with 1.0 eq. 2 and 1.0 eq. 8 at 0.2 M in DCM;

b

Isolated yield.

c

Enantioselectivities were determined by chiral HPLC;

d

Single alkylation product was the main product.

e

The reaction was performed with 1.5 eq. 2 and 1.0 eq. 8;

f

Another portion of Pd2(dba)3CHCl3 (5 mol%), (R,R)-4 (15 mol%) was added after 1h.

g

Another portion of Pd2(dba)3CHCl3 (5 mol%), Rac-4 (15 mol%) was added after 3.5 h.