Synthesis of Phosphoramides for the Lewis Base-Catalyzed Allylation and Aldol Addition Reactions

Abstract

Both chiral and achiral phosphoramides of diverse structure were prepared from diamines by the coupling to phosphorus(V) or phosphorus(III) reagents. Several enantiopure 1,2-diphenyl-1,2-ethanediamine analogues have been prepared by the reductive coupling of the corresponding N-silylimine with NbCl(4)(THF)(2) and subsequent resolution by the formation of diastereomeric menthyl carbamates. (S,S)-N,N'-Di-(1-naphthyl)-1,2-diphenyl-1,2-ethanediamine 15 was prepared by the arylation of (S,S)-1,2-diphenyl-1,2-ethanediamine with naphthyl iodide.

Synthesis and Conformational Analysis of Saturated cis‐and trans‐1,3,2‐Benzodiazaphosphinine 2‐Oxides

“…[4,14] The cis and trans cyclohexane 1,3-diamines 3a,b and 4a,b required for the cyclization reactions were prepared by lithium aluminium hydride re-duction of the corresponding cis-and trans-2-aminocyclohexanecarboxamides (1a,b and 2a,b) (Scheme 1). [15,16] Diamines 6a,b, bearing a methyl substituent on the nitrogen atom adjacent to the cyclohexane ring, were synthesized by analogous reductions of the urethanes 5a,b derived from carboxamides 1a,b.…”

Phosphorus heterocycles: synthesis, spectroscopic study and X-ray crystallography of some new diazaphosphorinanes

“…Hutchins et al studied the conformational analysis of 1,3-diazaphosphorinanes as well as their 1 H-and 31 P NMR spectroscopy [3]. Synthesis, conformational properties, and crystal structures [4,5] of several diazaphosphorinanes were reported [6][7][8][9]. Investigations on doubly connected phosphorus cations were made in some 1,3-diazaphosphorinanes [10].…”

Enantiopure fluorous 1,2-diaryl-1,2-diaminoethanes: synthesis and applications in asymmetric organometallic catalysis

“…Mp 118-120 °C (lit. 13 Determination of partition coefficients P. A 10 mL vial equipped with a magnetic stirrer was charged with the fluorous diamine 1 (50 mg), PFMC (2 mL) and the organic solvent (2 mL). The mixture was thermostatted at 25 °C and stirred vigorously for 4 h. A 1 mL sample was taken out of each phase, evaporated to dryness, and weighed on an analytical balance.…”

“…in a mixture of NH 3 /THF (5:4) at -78 °C, followed by acidic hydrolysis using aqueous HCl, gave stereoselectively the racemic primary diamine 4 in 89% yield. Reaction of this racemic diamine 4 with (-)-menthyl chloroformate in the presence of pyridine, according to Denmark's procedure 13 gave the corresponding bis-(menthyl carbamate) diastereoisomers (1R,2R)-5a and (1S,2S)-5b. Separation of these two diastereoisomers was performed by column chromatography, affording pure 5a and 5b in 32 and 19% yields, respectively.…”