1: With methanesulfonic acid; dimethylsulfide borane complex; (R)-tetrahydro-1-methyl-3,3-diphenyl-1H,3H-pyrrolo[1,2-c]-[1,3,2]oxazaborole in tetrahydrofuran; methanol; toluene T=-25 - 25°C; 2.5 - 2.75 h; 2: With hydrogenchloride; water in tetrahydrofuran; methanol; toluene T=0°C; 0.5 h; Product distribution / selectivity;