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Organic Synteses vol 69 - Paquette L.A.

Paquette L.A., Boecman R.K. Organic Synteses vol 69 - John Wiley & Sons, 1990. - 174 p.
ISBN 0-471-54560-0
Download (direct link): organicsynthesesvol691990.pdf
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116
applied method of ’masked acyl anion equivalents" for nucleophilic acylation.13 The present procedure finds only very limited applicability in the case of aryllithium/CO systems,14 but seems to be generally applicable to alkyllithium systems.
1. Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139.
2. (a) Gilman, H.; Cartledge, F. K. J. Organometal. Chem. 1964, 2, 447; (b) Kofron, W. G.; Baclawski, L. M. J. Org. Chem. 1976, 41,1879.
3. Seyferth, D.; Weinstein, R. M.; Wang, W.-L.; Hui, R. C. Tetrahedron Lett. 1983, 24, 4907.
4. Seyferth, D.; Weinstein, R. M.; Wang, W.-L. J. Org. Chem. 1983, 48,1144.
5. Weinstein, R. M.; Wang, W.-L.; Seyferth, D. J. Org. Chem. 1983, 48, 3367.
6. Seyferth, D.; Hui, R. C. Tetrahedron Lett. 1984, 25, 5251.
7. Seyferth, D.; Hui, R. C. J. Org. Chem. 1985, 50,1985.
8. Seyferth, D.; Hui, R. C. Tetrahedron Lett. 1984, 25, 2623.
9. Seyferth, D.; Hui, R. C. Organometallics 1984, 3, 327.
10. Seyferth, D.; Weinstein, R. M. J. Am. Chem. Soc. 1982, 104, 5534.
11. Seyferth, D.; Weinstein, R. M.; Wang, W. L.; Hui, R. C.; Archer, C. M. Isr. J. Chem.
1984, 24, 167.
12. Seyferth, D.; Hui, R. C.; Weinstein, R. M.; Wang, W.-L. Nova Acta Leopold.
1985, 59, 335; Chem. Abstr. 1988, 108, 6056t.
13. See the leading reviews of masked acyl anion equivalents for examples and references: (a) Hase, T. A.; Koskimies, J. K. Aldrichim. Acta 1981, 14, 73;
1982, 15, 35; (b) Lever, O. W., Jr. Tetrahedron 1976, 32, 1943; (c) Albright, J.
D. Tetrahedron 1983, 39, 3207; (d) Gröbel, B.-T.; Seebach, D. Synthesis 1977, 357.
117
14. Seyferth, D.; Wang, W.-L.; Hui, R. C. Tetrahedron Lett. 1984, 25,1651.
15. Dötz, K. H.; Wenicker, U.; Müller, G.; Alt, H. G.; Seyferth, D. Organometallics 1986, 5, 2570.
Appendix
Chemical Abstracts Nomenclature (Collective Index Number); (Registry Number)
3-Hydroxy-2,2,3-trimethyl-4-octanone: 4-Octanone, 3-hydroxy-2,2,3-trimethyl- (11); (85083-71-2)
Pinacolone: 2-Butanone, 3,3-dimethyl- (8,9); (75-97-8)
118
Table
Low Temperature, in situ. Direct Nucleoohilic Acvlation with the RLi/CO Reagent
Elect rophile (CH3)3SiCI O
II
R'-C-R"
0
R'-C-OR"
O
R'-C-NR"2
O
R'-C-SR"
O
R'-C-H
-£r°
Quench Reagent H20
H20
H20
H20
H£>
HaO
(CH3)3SiCI
Product
0
(CH3)3Si—C-R O
R-C-C(OH)R'R" O O
II II
R-C-C-R'
O O
II II
R-C-C-R'
O O
II II
R-C-C-R’
R-C-CH(OH)R'
.0 PSi(CH3)3 B-0<C-R
Reference
10
3,4
4
12
9
3
R'SSR'
n = 4,5
S3
COS
CS2
R'NCO
R'NCS
R'N=C=NR'
Fe(CO)5
H20
CH3I
CH3I
CH3I
CH3I
h2o
H20
CH3i
H20
R'-C-SR" + RSH 9
O
R'—C-S(CH2)nSCH3 9
O
R'-C-SCH3 9
O O
R-C-C-SCH3 8
O
R'—C-SCH3 8
O O
R-C-C-NHR' 6
O S
R-C-C-NHR' 6
O NR’
R-C-C-SCH3 6
O NR'
R-C-C-NHR' 7
(OC)4Fe=C.c,R (CH3)4N+ 15 (R = tert-Bu) q
119
PROPARGYLATION OF ALKYL HALIDES: SYNTHESIS OF (E)-6,10-DIMETHYL-5,9-UNDECADIEN-1-YNE AND (E)-7,11-DIMETHYL-6,10-DODECADIEN-2-YN-1-OL (5,9-Undecadien-1-yne, 6,10-dimethyl-, (E)-) and (6,lO-Dodecadlen-2-yn-i-ol, 7,11-dimethyl-, (E)-)
Submitted by John Hooz,1* Jorge Cabezas,2 Sergio Musmanni,2 and Jose Calzada.2* Checked by Hanno Wild, Andreas Weier, and Larry E. Overman.
+
2
A.
B.
a. (CH20),
rb. H20
120
1. Procedure
Caution! Allene and ethyl ether are highly volatile and flammable. Paraformaldehyde is a noxious material. The entire operation should be conducted in an efficient fume hood.
A. (E)-6,10-Dimethyl-5,9-undecadien-1-yne. An oven-dried (Note 1), 1-L, three-necked, round-bottomed flask is equipped with a large magnetic stirring bar (Note 2), a 250-mL pressure-equalizing addition funnel capped by a rubber septum (Note 3), a dry ice condenser capped by a rubber septum, and a rubber septum (capping the central neck) bearing a stainless steel cannula which serves as an argon inlet. The flask is charged with 190 mL of anhydrous ethyl ether (Note 4) and cooled to ca. -78°C using a dry ice-acetone bath. On a separate assembly (Note 5), allene gas (d at -40°C = 0.67 g/mL) from a compressed gas cylinder (Note 6) is condensed into a dry, 100-mL Pyrex graduated cylinder equipped with a 24/40 standard taper joint attached to a Claisen adapter and dry ice condenser (containing a slurry of dry ice-acetone) and cooled to -78°C with a bath of dry ice-acetone (Note 7). After 22.5 mL (375 mmol) of liquid allene has been collected, the adapter and condenser are removed and the graduated cylinder is capped with a rubber septum through which is inserted a cannula. The other end of this cannula is inserted through the rubber septum on the central neck to reach just below the surface of the cooled solvent. The allene is then transferred to the reaction vessel by removing the cylinder from the cooling bath. The temperature of the reaction vessel is maintained at -78°C, and a solution of 190 mL of 1.37 M butyllithium (260 mmol) in hexane (Note 8) is added dropwise over 1 hr through the addition funnel which is then rinsed with 5 mL of dry ether. The reaction mixture is allowed to warm gradually (over ca. 30 min) to -15°C and the white precipitate that forms is stirred an additional 15 min under an argon atmosphere. A solution of 12.9 g (75 mmol) of geranyl chloride (Note 9) in 40 mL of
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