Triethylamine → Bicyclo[2.2.1]hept-2-ene-1-carbonyl chloride

Temperature

3 °C

A 500 mL sulfur flask was equipped with magnetic stirring, addition funnel, thermometer, reflux condenser with N2-inlet adapter, and outlet adapter connected to a trap immersed in a dry ice/acetone bath. 58.28 g of 2-norbornene-5-carboxylic acid (Aldrich) were charged to the reactor under a positive flow of nitrogen, then 31.4 mL of thionyl chloride (51.32 g). 450 mL of methyl-tert-butyl ether were added, an ice bath was applied, and the contents of the reactor were stirred to mix and cool to 3° C. 51.6 mL of triethylamine (37.45 g) and 20 mL of MTBE were charged to the addition funnel and added dropwise to keep temperature less than 10° C. On completion of the addition the ice bath was removed and the flask was stirred for one hour. The resulting suspension was filtered to remove triethylamine hydrochloride. The resulting clear yellow solution was reduced to an oil on a rotary evaporator and purified by fractional distillation at 8 mBar (fraction boiling at 62-75° C.). 72% recovery at 99.13% purity was attained. The product was stored in a desiccator at room temperature until use.

1. customA 500 mL sulfur flask was equipped with magnetic stirring, addition funnel
2. temperaturethermometer, reflux condenser with N2-inlet adapter, and outlet adapter
3. customconnected to a trap
4. customimmersed in a dry ice/acetone bath
5. customan ice bath was applied
6. additionto mix
7. additionadded dropwise
8. customtemperature less than 10° C
9. customwas removed
10. stirringthe flask was stirred for one hour
11. filtrationThe resulting suspension was filtered
12. customto remove triethylamine hydrochloride
13. customThe resulting clear yellow solution was reduced to an oil on a rotary evaporator
14. distillationpurified by fractional distillation at 8 mBar (fraction boiling at 62-75° C.)
15. customThe product was stored in a desiccator at room temperature until use

ORD record

ord-883de1e9fd7c4e7f91732c214eb92ae2

Source dataset

uspto-grants-2011_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08003710B2