Methyl Methacrylate → 1,2,2,3-Tetramethylpiperidine

An oven-dried, 3-neck, 250-mL flask equipped with mechanical stirrer, rubber septum inlet, thermometer, and an argon atmosphere was charged with tetrahydrofuran (THF) (100 mL, freshly distilled from lithium aluminum hydride) and 2,2,6,6-tetramethylpiperidine (1.69 mL, 0.01 mol, distilled from NaOH and stored over molecular sieves under argon). n-Butyllithium (6.25 mL of a 1.6M solution in hexane, 0.01 mol) was added to the solution at 23°-27°; the resulting solution was stirred 15 min and then cooled to below -70° in a dry ice-acetone bath. To this solution containing 2,2,6,6-tetramethylpiperidinyllithium was added dropwise methyl methacrylate (10.7 mL, 0.1 mol, filtered through 10 wt % neutral alumina) over 15 min at -78° to -70°. The solution was warmed and poured into water (1.5 L); the precipitated polymer was isolated and dried, and then taken up and precipitated into hexane (1.5 L) from an acetone (75 mL) solution. After drying, 10.1 g (88% yield) of tetramethylpiperidine-ended polymethyl methacrylate (PMMA) was recovered; GPC analysis showed: Mn 1400, Mw 1700 (mol wt 1140 by design).

1. customAn oven-dried, 3-neck, 250-mL flask equipped with mechanical stirrer, rubber septum inlet
2. temperaturecooled to below -70° in a dry ice-acetone bath
3. temperatureThe solution was warmed
4. customthe precipitated polymer was isolated
5. customdried
6. customprecipitated into hexane (1.5 L) from an acetone (75 mL) solution
7. customAfter drying

ORD record

ord-a90f7261e3284f94b95e9fa53308cc65

Source dataset

uspto-grants-1986_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04590252