Synthesis of tertiary phosphine derivatives of dihydrophenophosphazine

Abstract

3.9-Dimethoxy-7iT-benzo[c]fluorene (7). The aldehyde 6 (400 mg) was stirred with PPA [prepared from P208 (10 g) and H3P04 (6 mL)] at 90 °C for 2 h. The reaction mixture was decomposed with ice and the product extracted with ether (2 x 30 mL). Purification by TLC (ethyl acetate/hexane, 1:4) afforded 7: 175 mg (46%); mp 175-177 °C (methanol-hexane); NMR

Preparation, reactions, structures, and possible uses of 5,10-dihydrophenophosphazine derivatives

“…They also found that the chemical shifts of the phosphine oxides 33a and 33b in CDC13 were +9.4 and +5.0 ppm, respectively. In another paper34 from the same laboratory, the chemical shifts of the thionophosphinyl chloride 24 and the tertiary phosphine sulfide 36b were reported to be +48.6 (THF) and +57.9 ppm (CDC13), respectively. Negrebetskii75 has studied the 13C NMR spectra of the tertiary phosphine 73 and its oxide 33a.…”

Facile Synthesis of Nitrogen-Containing Six-Membered Benzofuzed Phenophosphazinine Oxides and Studies of the Photophysical Properties

“…More recently, Tobisu and co-workers elegantly utilized nickel catalysis to cleave two C–P bonds . Unfortunately, the efficient synthesis of six-membered benzofuzed phosphacycles, , especially the nitrogen-containing phosphacycles, still remains a significant synthetic challenge. The classic reaction of organometallic reagents with P–X to afford six-membered phosphacycles was extremely scarce (Scheme b) because the incorporation of two aromatic halides in one molecule sometimes was synthetically difficult.…”

“…Unfortunately, the efficient synthesis of six-membered benzofuzed phosphacycles, , especially the nitrogen-containing phosphacycles, still remains a significant synthetic challenge. The classic reaction of organometallic reagents with P–X to afford six-membered phosphacycles was extremely scarce (Scheme b) because the incorporation of two aromatic halides in one molecule sometimes was synthetically difficult. Very recently, a bislithiation strategy of aryl bromide followed by a trap with PhPCl 2 was reported by Samsung Display Co.; however, both aromatic rings should be exactly the same, which prevents the efficient nitrogen-containing six-membered phosphacycle derivative synthesis .…”