220047-55-2

Upstream product

• 121911-32-8 1-[(E)-3-(benzyloxy)prop-1-enylsulfonyl]benzene 
• 218933-98-3 (2R,2'S)-3-benzyloxy-2-[(2'-(methoxymethyl)pyrrolidin-1'-yl)amino]propyl phenyl sulfone 
• 175229-12-6 (R)-3-benzyloxy-2-(tert-butoxycarbonylamino)propyl phenyl sulfone 

Downstream Products

• 175229-12-6 (R)-3-benzyloxy-2-(tert-butoxycarbonylamino)propyl phenyl sulfone 
• 220047-57-4 ((R)-2-Benzenesulfonyl-1-benzyloxymethyl-ethyl)-((S)-2,2-dimethyl-[1,3]dioxolan-4-ylmethyl)-amine 
• 212266-70-1 Toluene-4-sulfonic acid (S)-3-[((R)-2-benzenesulfonyl-1-benzyloxymethyl-ethyl)-benzyl-amino]-2-hydroxy-propyl ester 
• 212266-68-7 ((R)-2-Benzenesulfonyl-1-benzyloxymethyl-ethyl)-benzyl-((S)-2,2-dimethyl-[1,3]dioxolan-4-ylmethyl)-amine 
• 212266-69-8 (S)-3-[((R)-2-Benzenesulfonyl-1-benzyloxymethyl-ethyl)-benzyl-amino]-propane-1,2-diol 
• 220047-69-8 (2R,3S,4R)-3-Benzenesulfonyl-2-benzyloxymethyl-4-hydroxymethyl-pyrrolidine-1-carboxylic acid tert-butyl ester 
• 220047-66-5 ((3R,4S,5R)-4-Benzenesulfonyl-1-benzyl-5-benzyloxymethyl-pyrrolidin-3-yl)-methanol 
• 220047-97-2 (2R,3S,4R)-3-Benzenesulfonyl-2,4-bis-hydroxymethyl-pyrrolidine-1-carboxylic acid tert-butyl ester 
• 220047-60-9 Toluene-4-sulfonic acid (S)-3-[((R)-2-benzenesulfonyl-1-benzyloxymethyl-ethyl)-tert-butoxycarbonyl-amino]-2-hydroxy-propyl ester 
• 220047-59-6 ((R)-2-Benzenesulfonyl-1-benzyloxymethyl-ethyl)-((S)-2,3-dihydroxy-propyl)-carbamic acid tert-butyl ester 
• 220047-61-0 ((R)-2-Benzenesulfonyl-1-benzyloxymethyl-ethyl)-(S)-1-oxiranylmethyl-carbamic acid tert-butyl ester 
• 220047-82-5 (2S,4R)-1-tert-butoxycarbonyl-2-benzyloxymethyl-4-[2'-N-(tert-butoxycarbonyl)amino]ethylpyrrolidine 
• 220047-58-5 (S)-3-((R)-2-Benzenesulfonyl-1-benzyloxymethyl-ethylamino)-propane-1,2-diol 
• 220047-88-1 (2S,4R)-2-Benzyloxymethyl-4-(tert-butyl-dimethyl-silanyloxymethyl)-pyrrolidine-1-carboxylic acid tert-butyl ester 

Relevant academic research and scientific papers

Asymmetric synthesis of α-substituted β-amino sulfones by aza-Michael addition to alkenyl sulfones and subsequent α-alkylation

The aza-Michael addition of enantiopure 1-aminopyrrolidines to (E)- alkenyl sulfones in the presence of a catalytic amount of ytterbium trifluoromethanesulfonate [Yb(OTf)3] yields β-hydrazino sulfones in moderate to good yields and with diastereoselectivities of up to 98%. The latter undergo reductive N-N bond cleavage with BH3 · THF and, after N- protection with Boc2O or benzyl bromide, afford N-protected β-amino sulfones with moderate to high enantiomeric excesses (ee = 42 to ≥96%) without racemization. Subsequent α-alkylation of the N,N-dibenzyl protected β-amino sulfones with various electrophiles yields α-alkyl-β-amino sulfones in excellent yields (88-97%) with high diastereomeric (de ≥96 to ≥98%) and enantiomeric purity (ee = 94 to ≥96%). The absolute configuration of the new stereogenic centre was determined by X-ray structural analysis and confirmed by NMR spectroscopy (NOE experiments). Possible reaction mechanisms for the conjugate addition and α-alkylation are presented.

Asymmetric synthesis of α-substituted β-amino sulfones by aza-Michael addition/α-alkylation

The aza-Michael addition of (S)-1-amino-2-methoxymethyl-pyrrolidine (SAMP) to alkenyl sulfones (E)-1, followed by reductive N-N bond cleavage with BH3 · THF and N-benzylation yields N-benzyl-protected β-amino sulfones (R)-3 with high enantiomeric excesses (ee≥96%). Subsequent α- alkylation of (R)-3 with various electrophiles leads to α-alkyl-β-amino sulfones (R,R)-4a-e in excellent yields (88-97%) and finally high diastereomeric (de = 96-≥98%) and enantiomeric purity (ee≥96%). The absolute configuration was determined by X-ray structural analysis and confirmed by NMR spectroscopy (NOE-experiments).

Asymmetric synthesis of 4-substituted prolines as conformationally constrained amino acid analogues

Treatment of readily available chiral building block 1 with (2R)-2,3-O- isopropylideneglyceraldehyde (5) provides a new route for asymmetric synthesis of 2,4-disubstituted pyrrolidines. Several proline-amino acid chimeras: proline-leucine, proline-lysine, proline-arginine and proline- glutamic acid, are synthesized in highly diastereomerically pure forms.

Efficient N-N bond cleavage of chiral trisubstituted hydrazines with BH3·THF

Cleavage of the N-N bond of chiral trisubstituted hydrazines 1 with excess BH3·THF complex gives the corresponding optically active amines 2 in moderate to excellent yields and with high enantiomeric purity. This racemization and epimerization free cleavage procedure is compatible with functionalities sensitive to reductive cleavage conditions.