4-Toluenesulfonyl chloride → ((1S,3'R,4'S,5'S,6'R)-5-chloro-6-(4-ethylbenzyl)-3',4',5'-trihydroxy-3',4',5',6'-tetrahydro-3H-spiro[isobenzofuran-1,2'-pyran]-6'-yl)methyl 4-methylbenzenesulfonate

Participants

Reaction Steps

To a stirred solution of (1S,3′R,4′S,5′S,6′R)-5-chloro-6-(4-ethylbenzyl)-6′-(hydroxymethyl)-3′,4′,5′,6′-tetrahydro-3H-spiro[isobenzofuran-1,2′-pyran]-3′,4′,5′-triol (0.15 g, 0.356 mmol) in 3.5 mL of 2,6-lutidine was added p-toluenesulfonyl chloride (0.34 g, 1.78 mmol). After stirring for 21 h at ambient temperature, the solvent was distilled off. The residue was taken up with 30 mL of ethyl acetate, washed with 1 M hydrochloric acid and brine prior to drying over Na2SO4. Concentration under reduced pressure provided the crude product, which was purified by preparative TLC to give 135 mg of title compound. 1H NMR (CD3OD, 400 MHz) δ 7.61 (d, J=8.0 Hz, 2H), 7.35 (s, 1H), 7.21 (s, 1H), 7.16 (d, J=8.4 Hz, 2H), 7.11 (d, J=8.8 Hz, 4H), 5.02 (d, J=12.8 Hz, 1H), 4.97 (d, J=12.8 Hz, 1H), 4.22-4.08 (m, 4H), 3.90-3.86 (m, 1H), 3.71-3.65 (m, 2H), 3.39-3.34 (m, 1H), 2.59 (q, J=7.6 Hz, 2H), 2.33 (s, 3H), 1.18 (t, J=7.6 Hz, 3H); LC-MS (m/z) 575 [(M+1)+], 619 [(M+45)−].

Provenance & Evidence