N-Sulfinylpyrrolidine-containing ureas and thioureas as bifunctional organocatalysts

• Viera Poláčková,
• Dominika Krištofíková,
• Boglárka Némethová,
• Renata Górová,
• Mária Mečiarová and
• Radovan Šebesta

Beilstein J. Org. Chem. 2021, 17, 2629–2641, doi:10.3762/bjoc.17.176

• pre-catalysts (S,R)-5a and (S,S)-5a A stirred solution of (R)-tert-butanesulfinamide or (S)-tert-butanesulfinamide (0.09 g, 0.75 mmol) in THF (5 mL) was cooled to 0 °C under argon atmosphere. Butyllithium in hexane (0.35 g, 0.82 mmol) was added dropwise, and the solution was stirred for 15 min. The

• , 2973, 1653, 1159, 1237, 1058 cm−1; HRMS (m/z): [M + Na]+ calcd for C15H29N3O3S2, 386.1543; found, 386.1543; [M + H]+ calcd, 364.1729; found, 364.1722. General procedure for the preparation of N-sulfinylurea pre-catalysts (S,R)-5b and ((S,S)-5b) A stirred solution of (R)-tert-butanesulfinamide or (S

N-tert-Butanesulfinyl imines in the asymmetric synthesis of nitrogen-containing heterocycles

• Joseane A. Mendes,
• Paulo R. R. Costa,
• Miguel Yus,
• Francisco Foubelo and
• Camilla D. Buarque

Beilstein J. Org. Chem. 2021, 17, 1096–1140, doi:10.3762/bjoc.17.86

• key intermediate in the biomimetic synthesis of natural alkaloids. Interestingly, amino allylation of 5-bromopentanal (114) with (R)-tert-butanesulfinamide and allyl bromide (113, R = H) in the presence of indium metal gave homoallylamine derivative 115. In this transformation, imine (RS)-109 is a

An investigation of the observed, but counter-intuitive, stereoselectivity noted during chiral amine synthesis via N-chiral-ketimines

• Thomas C. Nugent,
• Richard Vaughan Williams,
• Andrei Dragan,
• Alejandro Alvarado Méndez and
• Andrei V. Iosub

Beilstein J. Org. Chem. 2013, 9, 2103–2112, doi:10.3762/bjoc.9.247

• Scheme 2. (Note: For similar discussions regarding the discrepancy of cis/trans chiral sulfinimine ratios and their corresponding amine product diastereomeric excesses, albeit using hydride reagents for the reduction, see the use of the (S)- and (R)-(+)-tert-butanesulfinamide (t-BuS(O)NH2) auxiliary

A novel asymmetric synthesis of cinacalcet hydrochloride

• Veera R. Arava,
• Laxminarasimhulu Gorentla and
• Pramod K. Dubey

Beilstein J. Org. Chem. 2012, 8, 1366–1373, doi:10.3762/bjoc.8.158

• )-tert-butanesulfinamide and regioselective N-alkylation of the naphthyl ethyl sulfinamide intermediate is described. Keywords: asymmetric synthesis; (R)-tert-butanesulfinamide; cinacalcet hydrochloride; naphthyl ethyl sulfinamide; regioselective N-alkylation; Introduction Cinacalcet hydrochloride

• ][16][17][18][19][20]. In our quest to utilize the chiral tert-butanesulfinamides in asymmetric syntheses of chiral amine APIs in an industrial setting [21][22][23], we report a novel asymmetric synthesis of 1 (Scheme 1) based on (R)-tert-butanesulfinamide (2), which was developed and extensively

• procedures for 1 (Scheme 7). Finally, hydrolysis of 7 dissolved in MTBE with conc. HCl at ambient temperature liberated the pure 1 (Scheme 8). Conclusion In summary, a novel stereoselective and short synthesis of (R)-cinacalcet hydrochloride by the application of (R)-tert-butanesulfinamide and regioselective