Propanal → Hept-3-yne-2,5-diol
Reaction equation
[CH:1]#[C:2][CH:3]([OH:5])[CH3:4].[CH:6](=[O:9])[CH2:7]C.[CH2:10]([Mg]Br)C>>[CH3:7][CH:6]([OH:9])[C:1]#[C:2][CH:3]([OH:5])[CH2:4][CH3:10]Participants
4
Procedure
0.5 mole of 1-butyn-3-ol was coupled with 0.5 mole of propionaldehyde under the influence of ethylmagnesium bromide according to Bull.Soc.Chim.(Fr.) 425 (1956) and 3-heptyne-2,5-diol (b.p. 109°-110° C at 2 mm Hg) was obtained in 64% yield. The alkyne diol was esterified with p-toluene sulfonylchloride as described in Example 1A and 3-heptyne-2,5-ditosylate (m.p. 69.5°-70.5° C) was obtained in 76% yield. The alkyne ditosylate was oxidised with aqueous potassium permanganate as described in Example 2A, at a temperature of 5° C and heptane-3,4-dione-2,5-ditosylate was obtained in 55% yield; m.p. 120°-121.5° C (from tetrachloromethane).
Sources & evidence
- ORD record
- ord-c26838695c924f92bfb76ca33b9e2b45
- Source dataset
- uspto-grants-1977_04
- Patent number
- US04020170
Reaction notes
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