Michael Additions of Metalated Thioacetals to Cyclic Enones†
First published: January 1975
No abstract is available for this article.
- 1(a) Cyanohydrin derivatives:
H. Stetter and
M. Schreckenberg,
Angew. Chem.
85, 89
(1973);
Angew. Chem. internat. Edit.
12, 81
(1973);
Tetrahedron Lett.
1973, 1461:
Chem. Ber.
107, 210
(1974);
E. Leete,
M. R. Chedekel, and
G. B. Bodem,
J. Org. Chem.
37, 4465
(1972);
(b) Cuprates of thioacetals:
T. Mukaiyama,
K. Narasaka, and
M. Furusato,
J. Amer. Chem. Soc.
94, 8641
(1972);
(c) Anions of thioacetal monosulfoxides:
R. H. Schlessinger et al.,
Tetrahedron Lett.
1973, 2595, 2599, 2603, 3267, 3271, 3275;
(d) Nitroalkane anions:
J. E. McMurry et al.,
J. Amer. Chem. Soc.
93, 5309
(1971);
J. Org. Chem.
38, 4367
(1973);
J. Org. Chem.
39, 258, 259
(1974);
(e) Carbonylnickel derivatives:
E. J. Corey and
L. S. Hegedus,
J. Amer. Chem. Soc.
91, 4926
(1969);
(f) Anions of oxazolones:
W. Steglich et al.,
Angew. Chem.
83, 725, 727
(1971);
Angew. Chem. internat. Edit.
10, 653, 655
(1971).
- 2
In the Michael additions described in ref. [1c], further stabilized anions derived from thioacetals are employed.
- 3
(a) For production of (1a), see ref. [4a]. For preparation of (1b), (CH3S)2CHLi [4] is reacted with chlorostannanes and the resulting (CH3S)2CHSnR3 is metalated with lithium diisopropylamide in THF/HMPA at −78 to −30°C. (b) Prior to transmetalation of (3) to (5) (CH3Li at −100°C) the diisopropylamine is distilled off with the major portion of the THF (replaced later) at 0°C bath temperature and 0.001 torr pressure.
- 4(a) Lithiated silylthioacetals:
D. Seebach,
M. Kolb, and
B.-Th. Gröbel,
Chem. Ber.
106, 2277
(1973).
(b) Lithiated stannyldithianes:
I. Willert and
B.-Th. Gröbel, Universität Giessen, 1973 (hitherto unpublished).
- 5For (R3Sn)2CCl2+RLi → (R3Sn)CCl2Li, see:
D. Seyferth,
F. M. Armbrecht jr., and
E. M. Hanson,
J. Organometal. Chem.
10, P-25
(1967);
(R3Sn)CBr3+RLi → (R3Sn)CBr2Li:
D. Seyferth et al.,
J. Organometal. Chem.
44, 299
(1973).
