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Modular Synthesis of Novel Chiral Phosphorous Triamides Based on (S)‐N‐(Pyrrolidin‐2‐ylmethyl)aniline and Their Application in Asymmetric Catalysis

“…Treatment of the diastereomeric mixture 7 with various secondary amines afforded ligands L1 – L11 with high diastereomeric purities and in good to excellent yields (Table 1). Although the major epimer of the starting chlorodiaminophosphane 7 has a syn configuration, all the resulting PTAs are obtained predominantly as anti diastereomers, in accordance with related previously reported PTAs 12,13,17. Ligands L1 – L11 show sharp signals in their 1 H, 13 C and 31 P NMR spectra, and no variation in their relative peak intensities was observed on standing either as solids or in solution, excluding epimerisation processes.…”

“…The chlorodiaminophosphane 7 was first synthesised by treatment of ( S )‐ N ‐(pyrrolidin‐2‐ylmethyl)aniline ( 6 ) with PCl 3 by a literature procedure 17. Although the formation of 7 was reported to proceed with complete stereoselection,17 in our hands compound 7 was repeatedly obtained as a mixture of the two diastereomers 7a and 7b (Figure 2) in a ratio of 3.5:1 as indicated by 31 P NMR spectroscopy ( δ = 153.9 ppm and 145.3 ppm, respectively). Because racemisation of the starting enantiomerically pure diamine under the reaction conditions could be excluded, the two diastereomers must be epimers at the phosphorus.…”

“…(3a S )‐1‐Chloro‐2‐phenyl‐hexahydro‐1 H ‐pyrrolo[1,2‐ c ][1,3,2]diazaphosphole (7): The synthesis was carried out from ( S )‐ N ‐(pyrrolidin‐2‐ylmethyl)aniline by the procedure described in the literature 17 …”

P‐Chiral Monodentate Diamidophosphites − New and Efficient Ligands for Palladium‐Catalysed Asymmetric Allylic Substitution

“…13 C NMR (100.61 MHz) and 31 The ees of 11aϪc and 13 were measured by HPLC on a Bruker LC 41 apparatus, with use of (R,R)-WHELK-01 chiral columns for 11a and 13 [48,49] and Daicel Chiralcel OD-H for 11b and 11c. [50] Preparation of the Ligands (2R,5S)-1,3-Diaza-2-chloro-3-phenyl-2-phosphabicyclo[3 …”

A first P,N-bidentate phosphite with a chiral ketimine fragment. Catalytic properties of its RhI and PdII complexes in comparison with those of phosphine analogs

“…9 Rhodium complex 5 was pre pared and characterized in situ by spectroscopy in CHCl 3 as described earlier. 19 Catalyzed alkylation of allyl acetate 6 with methyl malonate and its catalyzed sulfonylation with sodium p toluenesulfinate were carried out according to the corresponding procedures. 20 The starting substrate 6 was prepared according to a known procedure.…”