J. Org. Chem., Vol. 43, No. 6, 1978 1279
Notes (1 1) R. W. Hoffmann, “Dehydrobenzene and Cycioalkynes”, Academic Press, New York, N.Y., 1967, Chapter 1. (12) J. A. Zoitewicz and J. F. Bunnett, J. Am. Chem. SOC., 87, 2640 (1965). (13) R. A. Rossi, R H. de Rossi, and A. F. L6pez, J. Am. Chem. Soc.,98, 1253 (1976). (14) It is unlikely that chloride ion comes from nucleophilic displacement by CH30- on the hydrazideor CB, because it is known that nucleophilicaromatic substitution with unactivated benzene rings is very slow, and this reaction was carried out at very low temperature and for a short time (30 min). (15) I. P. Fisher arid F. P. Lossing, J. Am. Chem. SOC.,85, 1018 (1963); R. S. Berry, J. Clardy, and M E. Schafer, Tetrahedron Lett., 1003, 1011 (1965); R. H. de Rossi, H. E. Bertorello,and R. A. Rossi, J. Org. Chem., 35, 3328, 3332 (1970); R. G. Bergman, Acc. Chem. Res., 8,25 (1973); S. Wawzomek and J. H. Wagenknecht, J. Electrochem. SOC.,110, 420 (1963). (16) P,. W. Hoffmann, Chem. Ber., 98, 222 (1965).
of (E)-2-ethyl-l-iodo-l-octene (eq 3).9 Sequential treatment of the iodide with n-butyllithium, triethylborane, and iodine a t low temperature leads t o a 75% yield of (E)-4-ethyl-3decene (eq 4).1° In view of these encouraging results, a number EtMgX
+ CuBr.Me,S
-
-45
OC
n-C,H,,C=CH t
60 min
-25 ‘C 3.5 h
Et\
12
I
,c=
