New Developments in EnantioselectiveBrønsted Acid Catalysis
235
Table 9 Scope of the asymmetric BINOL-phosphate imino-azaenamine reaction
Entry
24
R
Yield [%] a ee [%] b
1
a
73
77 d
2
b
81
90
3
c
78
82
4
d
82
85 (91) c
5
e
81
82
6
f
48
83
7
g
76
86
8
h
71
77
a Isolated yields after chromatography
b Enantioselectivities were determined by HPLC analysis
c After one recrystallization from hexane-dichloromethane
repertoire of enantioselective BINOL-phosphate catalyzed transformations using C-nucleophiles.