Cesium Carbonate-Promoted P-Alkylation of Phosphinecarboxamides

Abstract

An effective method for the P-alkylation of N-arylphosphinecarboxamides was demonstrated. Primary N-arylphosphinecarboxamides without additional protection underwent P-monoalkylation with various alkyl halides in the presence of cesium carbonate as a promoter. The reactivity of phosphinecarboxamides was also explored.

Key words

alkylation - phosphinecarboxamides - arylalkylphosphinecarboxamides - secondary phosphines - alkyl halides

• References and Notes

• 1a De Clercq E. Med. Res. Rev. 2011; 31: 118
• 1b Katti KV, Gali H, Smith CJ, Berning DE. Acc. Chem. Res. 1999; 32: 9
• 1c Queffélec C, Petit M, Janvier P, Knight DA, Bujoli B. Chem. Rev. 2012; 112: 3777
• 1d McManus HA, Guiry PJ. Chem. Rev. 2004; 104: 4151
• 1e Weber L. Angew. Chem. Int. Ed. 2002; 41: 563 ; Angew. Chem. 2002, 114, 583
• 1f Fleming JT, Higham LJ. Coord. Chem. Rev. 2015; 297: 127
• 1g Meeuwissen J, Detz R, Sandee AJ, de Bruin B, Siegler MA, Spek AL, Reek JN. H. Eur. J. Inorg. Chem. 2010; 2992
• 1h Clarke TP, Landis CR. Tetrahedron: Asymmetry 2004; 15: 2123
• 2 Jupp AR, Goicoechea JM. J. Am. Chem. Soc. 2013; 135: 19131
• 3 Faria EN, Jupp AR, Goicoechea JM. Chem. Commun. 2017; 53: 7092
• 4 Robinson TP, Goicoechea JM. Chem. Eur. J. 2015; 21: 5727
• 5 Geeson MB, Jupp AR, McGrady JE, Goicoechea JM. Chem. Commun. 2014; 50: 12281
• 6 Beddoe SV. F, Cosham SD, Kulak AN, Jupp AR, Goicoechea JM, Hyett G. Dalton Trans. 2018; 47: 9221
• 7 Quin LD. A Guide to Organophosphorus Chemistry . Wiley- Interscience; New York: 2000
• 8a Higham LJ. In Phosphorus Compounds: Advanced Tools in Catalysis and Material Sciences . Peruzzini M, Gonsalvi L. Springer; Dordrecht: 2011. Chap. 1, 1
• 9 Imamoto T, Oshiki T, Onozawa T, Kusumoto T, Sato K. J. Am. Chem. Soc. 1990; 112: 5244
• 10a Lebel H, Morin S, Paquet V. Org. Lett. 2003; 5: 2347
• 10b Blank NF, McBroom KC, Glueck DS, Kassel WS, Rheingold AL. Organometallics 2006; 25: 1742
• 10c Anderson BJ, Guino-o MA, Glueck DS, Golen JA, DiPasquale AG, Liable-Sands LM, Rheingold AL. Org. Lett. 2008; 10: 4425
• 11 Stewart B, Harriman A, Higham LJ. Organometallics 2011; 30: 5338
• 12 Wu Y.-H, Li Z.-F, Wang W.-P, Wang X.-C, Quan Z.-J. Eur. J. Org. Chem. 2017; 5546
• 13 Phosphinecarboxamides 3a–q; General Procedure The appropriate N-arylphosphinecarboxamide 1 (0.2 mmol) and haloalkane 2 (0.24 mmol, 1.2 equiv) were added to a sealed tube charged with a mixture of Cs₂CO₃ (0.2 mmol, 1 equiv) in DMSO (4 mL), and the resulting mixture was stirred at r.t. for 0.5 h. When the reaction was complete (TLC), H₂O (30 mL) was added and the mixture was extracted with EtOAc. The organic phase was separated, dried (MgSO₄), filtered, and concentrated. The crude product was purified by column chromatography [silica gel, PE–EtOAc (4:1)]. N-(4-Methoxyphenyl)-1-methylphosphinecarboxamide (3a) White solid; yield: 33 mg (85%); mp 75–76 °C. ¹H NMR (600 MHz, CDCl₃): δ = 7.69 (s, 1 H), 7.39 (d, J = 8.4 Hz, 2 H), 6.81 (d, J = 8.4 Hz, 2 H), 4.02 (dq, J = 206.4, 7.8 Hz, 1 H), 3.76 (s, 3 H), 1.36 (dd, J = 7.2, 3.0 Hz, 3 H). ¹³C NMR (150 MHz, CDCl₃): δ = 176.67 (d, J = 14.6 Hz), 156.48, 131.01 (d, J = 4.1 Hz), 121.80, 114.09, 55.44, 1.10 (d, J _C–P = 8.1 Hz, PCH₃). ³¹P NMR (162 MHz, CDCl₃): δ = –74.42. HRMS(ESI): m/z [M + H]⁺ Calcd for C₉H₁₃NO₂P: 198.0678; Found: 198.0679.
• 14 Wiedemann G. Ann. Phys. Chem. 1848; 150: 67
• 15 Jupp AR, Trott G, Payen de la Garanderie É, Holl JD. G, Carmichael D, Goicoechea JM. Chem. Eur. J. 2015; 21: 8015
• 16 Becker G, Hübler K, Niemeyer M, Seidler N, Thinus B. Z. Anorg. Allg. Chem. 1996; 622: 197