Design and Performance Validation of a Conductively Heated Sealed-Vessel Reactor for Organic Synthesis

Abstract

A newly designed robust and safe laboratory scale reactor for syntheses under sealed-vessel conditions at 250 °C maximum temperature and 20 bar maximum pressure is presented. The reactor employs conductive heating of a sealed glass vessel via a stainless steel heating jacket and implements both online temperature and pressure monitoring in addition to magnetic stirring. Reactions are performed in 10 mL borosilicate vials that are sealed with a silicone cap and Teflon septum and allow syntheses to be performed on a 2-6 mL scale. This conductively heated reactor is compared to a standard single-mode sealed-vessel microwave instrument with respect to heating and cooling performance, stirring efficiency, and temperature and pressure control. Importantly, comparison of the reaction outcome for a number of different synthetic transformations performed side by side in the new device and a standard microwave reactor suggest that results obtained using microwave conditions can be readily mimicked in the operationally much simpler and smaller conventionally heated device.

Deuterated Curcuminoids: Synthesis, Structures, Computational/Docking and Comparative Cell Viability Assays against Colorectal Cancer

“…Upon completion (monitored by TLC) the product was vacuum filtered, washed with ethyl acetate, and dried under vacuum. The corresponding deuterated curcuminoid 16 was prepared as previously described for 16 a , by addition of Na 2 C 2 O 4 (4 equiv) in 8:2 methanol/water in a Monowave reactor . The temperature was set to 140 °C and held for 10 min.…”

“…The corresponding deuterated curcuminoid 16 was prepared as previously described for 16 a, [9] by addition of Na 2 C 2 O 4 (4 equiv) in 8:2m ethanol/water in a Monowave reactor. [32] The temperature was set to 140 8Ca nd held for 10 min. Upon completion, the product was vacuum filtered, rinsed with deionized water and dried under high vacuum.…”

My Twenty Years in Microwave Chemistry: From Kitchen Ovens to Microwaves that aren't Microwaves

“…The basic concept was taken up by Anton Paar and led to the development of the Monowave 50 reactor (Figure ), an instrument that enables sealed vessel heating of 10 mL tubes to 250 °C and 20 bar pressure by applying conductive heating principles . It employed the same glass vessels as the Monowave 300 microwave reactor (cf .…”

“…It employed the same glass vessels as the Monowave 300 microwave reactor (cf . Figure ) and many of the design features of this instrument were implemented into this autoclave‐type reactor . Similar to the prototype instrument it essentially mimics what can be achieved in a standard single‐mode microwave reactor .…”

“…Figure ) and many of the design features of this instrument were implemented into this autoclave‐type reactor . Similar to the prototype instrument it essentially mimics what can be achieved in a standard single‐mode microwave reactor . Given its small footprint and low‐cost, we have recently implemented the Monowave 50 into our undergraduate organic chemistry teaching labs at the University of Graz…”