High Purity 1-Ethynyl-1-Cyclohexanol 99.5% CAS 78-27-3 Recrystallised Solid

Recrystallisation is where this grade comes from. The crude melt is dissolved, treated with carbon, filtered and crystallised slowly, which leaves the cyclohexanone and the diol by products in the mother liquor. What comes out is 99.5% with a melting range tight enough that the differential scanning calorimetry curve looks like a step rather than a slope.

Buyers choose it when the alkyne is going into a coupling with a palladium or copper catalyst. Those systems are sensitive to the aldehyde that forms when residual cyclohexanone oxidises in the pot, and to the diol that competes for the metal. Cutting both to trace level usually fixes a yield problem faster than changing the catalyst.

• 99.5% minimum by GC: clean coupling with palladium and copper systems that are sensitive to trace impurities
• Cyclohexanone under 0.1%: no aldehyde formation in the pot to poison the catalyst
• Diol impurity under 0.2%: no competing ligand for the metal centre
• Tight melting range: consistent melt and charge behaviour batch to batch
• Carbon treated and filtered: white product with no grey haze after dissolving
• Kilogram to drum: same lot available from 1 kg to 25 kg for scale up

Catalytic couplings on the terminal alkyne, cross coupling with aryl halides, and any step where the tertiary alcohol has to survive a metal catalysed reaction without acting as a ligand.

Charge as a melt into a dry pot, or dissolve in the reaction solvent first. Because the grade is recrystallised, it dissolves faster and clearer than the standard material, which shortens the charge time in a plant scale reactor.

1 kg aluminium bag, 5 kg foil bag, 25 kg fibre drum with double liner. Foil is used for the smaller packs because the solid picks up moisture and cakes if it is stored in a plain bag in a humid warehouse.

Store below 25 degrees C, dry, sealed and out of light. Air freight for 1 to 5 kg, sea freight for drums from Shanghai.

COA with assay, cyclohexanone, diol, water, melting range and colour of melt, plus the GC trace. A 100 g retention sample per lot is kept for 24 months.

SDS in GHS format and an elemental impurity statement on request. Custom recrystallisation to a tighter melting range can be quoted for defined projects.