To demonstrate the usefulness of our approach to catalytic selectivity, we applied it to the synthesis of the drug (R)-cinacalcet (4c), which is approved for the treatment of secondary hyperparathyroidism and hypercalcaemia. In almost all reported syntheses of this API, enantiopure (R)-1 has been used as a starting material (typically obtained by enzymatic resolution) to ensure only one enantiomer is produced (one exceptional report employs another enantiopure feedstock, (R)-tertbutanesulfinamide, to introduce an asymmetric C-N bond). Here we use our SPG-mediated approach to perform the stereoselective synthesis from a racemic starting material -the amine (S/R)-1and an a achiral aldehyde (2c) reported in a number of syntheses of (R)-cinacalcet -and achiral Amberlyst 15 as the catalyst for the enantioselective bondforming step. Scheme 2. Synthesis of (R)-Cinacalcet using SPG to impart selectivity. i) Amine 1 (0.1 mmol), aldehyde 2c (0.05 mmol), TIPS-β-CD (0.4 mmol) and toluene (2 mL), 15 min; (ii) Solid acid (50% mmol), 1 h; (iii) NaBH4 (0.20 mmol), 1h at -20 ˚C.