5-Hexyn-1-ol

CAS 928-90-5, 5-Hexyn-1-ol, enters the catalogue as a C6H10O alkyne with a molecular weight of 98.14.

Terminal alkynes also dimerise and oligomerise under the wrong conditions, so the copper and palladium loading of the coupling step is the thing to control.

The formula C6H10O resolves to 6 carbons with one oxygen. With 6 carbons the molecule is small enough to be lost to evaporation during a work-up, so the step is usually run closed.

Where this entry sits in a route

5-Hexyn-1-ol pairs a terminal alkyne with a primary alcohol six carbons apart, which is the geometry used to close five- and six-membered rings by enyne metathesis and to build tethers between two functional groups. It is one of the few short entries where both ends of the molecule can be addressed independently.

What the analysis covers

The lot is checked for the corresponding aldehyde and for the diyne that forms by oxidative homocoupling. The diyne is the impurity that matters in metathesis steps, because it competes for the catalyst.

Handling and storage

The container is kept sealed and out of light. Alkynes are checked for the coupled diyne before use, because that is the impurity that builds on standing.

Ordering

Quoted from stock in 1kg / 25kg / 100kg, or made to order where the lot has run down. Either way the same release testing applies. Identity is confirmed by NMR and MS at release, and the assay value belongs to the lot rather than to the catalogue entry.