Claisen adapter

Claisen Adapters for Multi-Neck Distillation Setups

You know that moment when you're running a distillation and realize you need to add reagents and monitor temperature at the same time? That's where a Claisen adapter becomes your best friend. It's basically a Y-shaped piece of borosilicate glass that turns one neck into two outlets, letting you connect multiple components without tearing down your entire setup.

Advanced Distillation Setup with Claisen Adapters

Three-way connectivity is what makes these adapters so useful in organic synthesis. The design features two upper female joints and one lower male joint, all with standard taper ground glass connections that seal tight under vacuum. I've used mine countless times for fractional distillation where you need a thermometer in one neck and an addition funnel in the other. If you're working with more complex separations, you might want to check out the Adapter Fractionation Connecting 75° with socket for angled configurations, though the straight Claisen design works better when vertical space isn't an issue.

Dual-Neck Configuration Benefits

• Simultaneous operations: Add reagents dropwise while monitoring internal temperature without interrupting your reaction
• Vacuum compatibility: Ground glass joints maintain seal integrity during reduced pressure distillations
• Thermal stability: Borosilicate 3.3 glass handles up to 500°C, though you'll rarely push it that far
• Easy integration: Works seamlessly with Rotary evaporators and standard glassware systems

The Adapter Bent 75° offers a different approach if you need angled connections, but you'll sacrifice some of the symmetry that makes Claisen adapters so predictable in complex setups.

Joint Size Compatibility Options

You'll find these in standard joint sizes: 14/20 for microscale work, 19/26 and 24/29 for typical bench-scale reactions, and 29/32 when you're scaling up. Wall thickness runs about 1.8-2.0mm, which gives you decent durability without making them too heavy. I'd recommend keeping at least two sizes in your glassware cabinet since you'll inevitably need both when setting up reactions with Glass Reactors or connecting to Circulating chillers and heaters for temperature-controlled processes.

Applications in Synthetic Chemistry

Reflux reactions are where these really shine. You can run a condenser on one neck and use the other for adding catalysts or monitoring progress. Vacuum distillations benefit too since you maintain system integrity while keeping access points open. Pharmaceutical synthesis often requires this kind of flexibility, especially during multi-step procedures where you can't afford to break vacuum or expose moisture-sensitive intermediates to air.