N,N,N',N'-Tetramethylethylenediamine → HCID 13037513, compound

Temperature

0 °C

Under a static nitrogen atmosphere at 26° C., a solution of n-butyllithium (3.93 g, 7.13 mol) in hexane was added to a solution of tetramethylethylenediamine (1.8 g, 0.0155 mol) in 30 ml. of anhydrous cyclohexane with constant stirring. The reaction mixture was cooled to 0° C. and then a solution of N-benzylaniline (5.5 g, 0.03 mol) in 30 ml. of anhydrous cyclohexane was added to the mixture to produce a suspension containing a dilithio compound. This suspension was stirred for 2.5 hours at 26° C. and then cooled to 0° C. A solution of t-butylphosphonic dichloride (5.6 g, 0.032 mol) in 30 ml. of anhydrous cyclohexane was added dropwise to the suspension and the resulting mixture was stirred for 1.5 hours at 26° C. The reaction mixture was cooled to 0° C. and then quenched with the rapid addition of 10 ml. of a saturated solution of ammonium chloride. The resulting mixture was concentrated in vacuo and the residue was partitioned in methylene chloride and water. The layers were separated and the methylene chloride layer was washed with 5% hydrochloric acid, then with water, dried over sodium sulfate and concentrated in vacuo to yield a red oil. The red oil was separated on a silica gel column using ethyl acetate as the eluant. Fractions containing the benzazaphosphole were combined and concentrated in vacuo to produce a crude product. The crude product was triturated with isopropyl ether and petroleum ether to yield a white solid. The white solid was recrystallized from isopropyl ether to yield 1-(t-butyl)-2-pheny-2,3-dihydro-1H-2,1-benzazaphosphole-1-oxide (0.7 g, 8% yield) as colorless needles having a melting point of 171°-172° C. and the following analysis:

1. customto produce a suspension
2. temperaturecooled to 0° C
3. stirringthe resulting mixture was stirred for 1.5 hours at 26° C
4. temperatureThe reaction mixture was cooled to 0° C.
5. customquenched with the rapid addition of 10 ml
6. concentrationThe resulting mixture was concentrated in vacuo
7. customthe residue was partitioned in methylene chloride
8. customThe layers were separated
9. washthe methylene chloride layer was washed with 5% hydrochloric acid
10. dry with materialwith water, dried over sodium sulfate
11. concentrationconcentrated in vacuo
12. customto yield a red oil
13. customThe red oil was separated on a silica gel column
14. additionFractions containing the benzazaphosphole
15. concentrationconcentrated in vacuo
16. customto produce a crude product
17. customThe crude product was triturated with isopropyl ether and petroleum ether
18. customto yield a white solid
19. customThe white solid was recrystallized from isopropyl ether

ORD record

ord-86e8e1017f074f5ebe6b70a0f207d7b3

Source dataset

uspto-grants-1982_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04319913