Also known as 1,4-pentadiyne
1,4-Pentadiyne (penta-1,4-diyne) is a chemical compound belonging to the alkynes. The compound is the structural isomer to 1,3-pentadiyne. == Preparation == Until the late 1960s, no successful synthesis of this seemingly simply preparable molecule was described. Although long-chain and more complex 1,4-diynes had been synthesized successfully before, synthesis approaches starting from sodium acetylide or the acetylene Grignard reagent and propargyl bromide or methylene chloride failed, even with the inclusion of copper(I) chloride. Mostly 1,3-pentadiyne was obtained as rearrangement product.
1,4-Pentadiyne (penta-1,4-diyne) is a chemical compound belonging to the alkynes. The compound is the structural isomer to 1,3-pentadiyne. == Preparation == Until the late 1960s, no successful synthesis of this seemingly simply preparable molecule was described. Although long-chain and more complex 1,4-diynes had been synthesized successfully before, synthesis approaches starting from sodium acetylide or the acetylene Grignard reagent and propargyl bromide or methylene chloride failed, even with the inclusion of copper(I) chloride. Mostly 1,3-pentadiyne was obtained as rearrangement product.
The first successful isolation reacted propargyl bromide and ethynylmagnesium bromide, with a copper(I) chloride catalyst in THF. This gave a 70% yield in solution, but the product was difficult to separate from the solvent. Compared to previous attempts, the successful approach included an additional round of flash distillation and gas-liquid chromatography of the distillate.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).