Diethyl Ether → Chloro-n,n-diisopropylamino-2-(4-nitrophenyl)ethoxy-phosphane

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Reaction Steps

p-Nitrophenylethanol (4.16 g; 25 mmole) was added portion wise to a solution of freshly distilled PCl3 (14 ml; 0.16 mole) in absolute ether (40 ml) at -30° C. under a nitrogen atmosphere within 45 min. The reaction mixture was stirred at r.t. for 1.5 h and the solvent and excess PCl3 were then removed in vacuo at 0° C. The residue was treated with N,N-diisopropyl-trimethylsilylamine (Preparation 5a) (4.33 g; 25 mmole) at 0° C. under a nitrogen atmosphere for 30 min and then at r.t. for 20 h. The resulting trimethylsilyl chloride was removed under high vacuum at r.t. to yield a syrupy pale yellow product (7.1 g; 85%) which crystallized upon storage at -20° C. This material was then used for the subsequent phosphitylation reactions. 1H-NMR (CDCl3): 8.1-8.2 (m, 2H, o to NO2); 7.39-7.43 (m, 2H, m to NO2); 4.04-4.18 (m, 2H, P--O--CH2); 3.63-3.79 (m, 2H, N--CH); 3.07-3.13 (t, 2H, P--O--C--CH2); 1.14-1.27 (2d, 12H, N--C--CH3). 31P-NMR (CDCl3): 181.60 ppm.

Provenance & Evidence