Diisopropylethylamine → Retinol phosphoramidite

All-trans-retinol (1 g) was vacuum dried and dissolved in anhydrous CH2Cl2 (10 ml) in an argon atmosphere. Diisopropylethylamine (2.65 ml, 21.5 mmol) was syringed in and the reaction mixture was cooled in an ice-bath. 2-cyanoethyl-N,N-diiso-ropylchlorophosphoramidate (2.5 g, 2.45 ml, 10.5 mmol) was slowly added by syringe under argon atmosphere. The reaction mixture was stirred for 30 min. at which time TLC (CH2Cl2:CH3OH:Et3N, 90:10:0.1) indicated complete conversion of the alcohol to its phosphoramidite. The reaction mixture was added to 100 ml of saturated NaHCO3 followed by washing the reaction flask with (2×25 ml) CH2Cl2. The CH2Cl2 layer was separated and washed with 100 ml of saturated NaCl solution and dried over anhydrous MgSO4 and evaporated into a yellow foam. The amidite was used directly in the DNA synthesizer without further purification since decomposition of this amidite was noted upon silica column purification.

1. customdried
2. dissolutiondissolved in anhydrous CH2Cl2 (10 ml) in an argon atmosphere
3. temperaturewas cooled in an ice-bath
4. addition2-cyanoethyl-N,N-diiso-ropylchlorophosphoramidate (2.5 g, 2.45 ml, 10.5 mmol) was slowly added by syringe under argon atmosphere
5. washby washing the reaction flask with (2×25 ml) CH2Cl2
6. customThe CH2Cl2 layer was separated
7. washwashed with 100 ml of saturated NaCl solution
8. dry with materialdried over anhydrous MgSO4
9. customevaporated into a yellow foam
10. customThe amidite was used directly in the DNA synthesizer without further purification since decomposition of
11. customthis amidite was noted upon silica column purification

ORD-Eintrag

ord-3baf4227016e4a6e994874a95370b550

Quelldatensatz

uspto-grants-2005_07

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06919439B2