DA-ME PHOSPHONAMIDITE synthesis

Yield:114079-05-9 91%

Reaction Conditions:

Stage #1: N,N-diisopropylamino methylphosphonamidic chloridewith N-ethyl-N,N-diisopropylamine in dichloromethane;toluene; for 0.0833333 h;
Stage #2: N₆-benzoyl-5'-O-(4,4'-dimethoxytrityl)-2'-deoxyadenosinewith 9-azajulolidine in dichloromethane;toluene; for 0.25 h;Reagent/catalyst;

Steps:

4; 10

General procedure: i) An activated resin obtained in Example 8 (AM-PS-Het5, 250 mg) was loaded into an HPLC column of stainless steel (75 mm x 4.6 mm). The resulting column packed with the activated resin was flushed with toluene at a flow rate of 1.00 mL/min for 15 minutes. The column was weighed (mToiuene + resin + column = 43.118 g), flushed with dichloromethane (DCM) with a flow rate of (0151) 1.00 mL/min for 15 minutes, and then weighted again (rriDCM + res n + column = 43.588 g). The void volume, Vvoid, of the system was determined to establish a connection between flow rate and estimated residence time of the liquid passing through the column. The void volume of the column was calculated using the formula: (0152) Am solvent switch 43.5588 g - 43.118 g (0153) ^void = 1.00 raL (0154) ^{1 3 0 867} wherein, Arrisoivent switch is the difference in mass and Apsoivent the difference in density when switching solvents, ii) a loaded resin was prepared by loading the activated resin 4 times with PCI (0.10 M) and L/,/V-diisopropylethylamine (DIPEA, 0.10 M) in DCM (2 mL) with flow rate of 1.00 mL/min for 5 minutes including DCM wash, iii) the substrate alcohol (0.10 M, 0.114 mmol) and DMAP (0.15 M, 0.171 mmol) or another base, such as PPY or 9AJ, were dissolved in DCM (1 mL) and eluted through the loaded resin with a flow rate of between 0.125 mL/min and 1.00 mL/min (residence time between 8 minutes and 1 minute), iV) fractions comprising the synthesized phosphoramidites were collected for 2.5 times the residence time.

References:

WO2022/13393,2022,A1 Location in patent:Page/Page column 36-38; 51-53