Formation of alkynes through double elimination of vicinal dibromides
Description: Sodium amide will convert 1,2-dihalides (“vicinal dihalides”) into alkynes through two consecutive elimination reactions.
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Real-Life Examples:
Org. Synth. 1926, 6, 26
DOI Link:10.15227/orgsyn.006.0026


Org. Synth. 1922, 2, 67
DOI Link:10.15227/orgsyn.002.0067


Org. Synth. 1938, 18, 3
DOI Link: 10.15227/orgsyn.018.0003


Org. Synth. 1932, 12, 60
DOI Link: 10.15227/orgsyn.012.0060


Org. Synth. 1942, 22, 50
DOI Link: 10.15227/orgsyn.022.0050


Org. Synth. 1958, 38, 70
DOI Link: 10.15227/orgsyn.038.0070


Org. Synth. 1950, 30, 72
DOI Link: 10.15227/orgsyn.030.0072


Org. Synth. 1957, 37, 77
DOI Link: 10.15227/orgsyn.037.0077


Org. Synth. 1952, 32, 104
DOI Link: 10.15227/orgsyn.032.0104


Org. Synth. 1979, 59, 10
DOI Link: 10.15227/orgsyn.059.0010


My course taught us that we need three molar equivalents of NaNH2 for this reaction, as it prevents the formation of the alkynyl salt.
True, for terminal alkynes. Once the alkyne is formed, it can then be deprotonated by NaNH2 in solution. For practical purposes, three equivalents for the formation of terminal alkynes is best.
Would this also work with geminal dihalides?
Yes, it should.
Does this work the same way for Geminal Dihalides?
Yes it does!