Skip to main content
. Author manuscript; available in PMC: 2010 Dec 11.
Published in final edited form as: Tetrahedron Asymmetry. 2009 Dec 11;20(23):2659–2665. doi: 10.1016/j.tetasy.2009.11.009

Table 2.

Reduction of heteroaryl ketones containing sulfur using 1and 10 mol % of spiroaminoborate ester 1.a

Entry Substrate Cat. 1
(%)		 Yieldb
(%)		 Eec
(%)
1 graphic file with name nihms160231t7.jpg 10 92 98
2 1 87 96
3 graphic file with name nihms160231t8.jpg 10 91(83)d 98 (99)d
4 1 91 98
5 graphic file with name nihms160231t9.jpg 10 75 97
6 1 86 (71)d 98 (82)d
7 graphic file with name nihms160231t10.jpg 10 90 (83)d 95 (99)d
8 1 89 96
9 graphic file with name nihms160231t11.jpg 10 92 (76)d 99(99)d
10 1 92 99
11 graphic file with name nihms160231t12.jpg 10 92(53)d 94.5(94)d
12 1 93 94
13 graphic file with name nihms160231t13.jpg 10 80c,d 93d
14 1 92 99 (92)d
15 graphic file with name nihms160231t14.jpg 10 85c 100
16 1 92 99
a

The reaction was carried out using 0.7 equiv of borane DMS in THF at room temperature.

b

Isolated yield after distillation in a Kugelrohr apparatus.

c

Determined by GC of the acetate on chiral column.

d

The reaction was carried out using BH3-DEA