The following information was retrieved from the publication:1,2-Addition of Trialkylaluminium Reagents on N-Diphenylphosphinoyl-ketimines in the Absence of Any Additional Reagents (authors: Rüdiger Reingruber and Stefan Bräse)Under a dry argon atmosphere, imine (0.5 mmol) was dissolved in 1.0 mL of dry toluene and stirred for 30 minutes at 25 ⁰C to give a homogenous solution. Then AlEt3 (4.0 equiv.), used as a 1 M solution in toluene or hexane, was added under argon and the reaction mixture was stirred further. After all of the starting material was consumed, the mixture was quenched by addition of methanol and saturated solution of K-Na-tartrate. The aqueous layer was extracted with ethyl acetate (3 × 5 mL), dried over MgSO4 and filtered. The filtrate was concentrated under reduced pressure. The product was obtained in high purity without further purification in 99% yield. 1H NMR (400 MHz, CDCl3, ppm) δ = 7.85–7.73 (m, 4 H, P(=O)-Aro-H), 7.47–7.32 (m, 6 H, P(=O)-Arm-H u. Arp-H), 7.23 (dd, 1 H, O-CH, J = 1.8 Hz, J = 0.8 Hz), 6.16 (dd, 1 H, O-C=CH-4, J = 3.2 Hz, J = 1.8 Hz), 6.05 (dd, 1 H, O-C=CH-3, J = 3.2 Hz, J = 0.8 Hz), 3.33 (bd, 1 H, NH, J = 7.2 Hz), 2.06–1.97 (m, 2 H, CH2), 1.57 (s, 3 H, C-CH3), 0.78 (t, 3 H, CH2-CH3). 13C NMR (100 MHz, CDCl3, ppm) δ = 157.2 u. 157.2 (Cq, C1-OAr), 140.2 (+, C4-OAr), 134.3 u. 133.0 [Cq, 2 × C-P(=O)], 131.0 u. 130.9 [+, 2 × C4-P(=O)-Ar], 130.5 u. 130.4 [(+, 2 × C2- u. C6-P(=O)-Ar], 127.4 u. 127.3 [+, 2 × C3- u. C5-P(=O)-Ar], 108.9 (+, C2‑OAr), 104.8 (+, C3-OAr), 56.0 (Cq, d, C-NH, J = 2.4 Hz), 35.1 (–, d, CH2, J = 4.2 Hz), 23.2 (+, d, C-CH3, J = 3.8 Hz), 8.8 (+, CH2-CH3. IR (KBr): = 3196 (br), 3057 (m), 2977 (m), 2937 (m), 2879 (w), 1592 (w), 1503 (m), 1437 (m), 1375 (m), 1294 (m), 1234 (m), 1192 (m), 1123 (m), 1053 (m), 1011 (m), 962 (m), 923 (m), 868 (m), 800 (m), 748 (m), 724 (m), 697 (m), 566 (m), 540 (m) cm-1. MS (70 eV, EI), m/z (%): 339 (6) [M+], 311 (20), 310 (100), 201 (54), 77 (8).
