Acetic Acid → 3beta-(Tert-butyldimethylsilyl)oxy-1alpha-(methoxymethyl)oxypregna-5,7-diene-20-carbaldehyde

Participants

Reaction Steps

In 5 ml of tetrahydrofuran was dissolved 20-(5,5-dimethyl-1,3-dioxan-2-yl)-3β-(tert-butyldimethylsilyl)oxy-1α-(methoxymethyl)oxypregna-5,7-diene, followed by addition of 5 ml of 80% acetic acid. The mixture was refluxed in an atmosphere of argon gas for 12 hours. The reaction mixture was then worked up in the same manner as Example 156 to give 50 mg of 3β-(tert-butyldimethylsilyl)oxy-1α-(methoxymethyl)oxypregna-5,7 -diene-20-carbaldehyde showing the following physical properties. 1H-NMR spectrum (90 MHz) δTMSCDCl 3: 0.13 (s, 6H), 0.66 (s, 3H), 0.95 (s, 9H), 1.01 (s, 3H), 1.14 (d, J=6.2 Hz, 3H), 3.40 (s, 3H), 4.10-4.50 (2H), 4.80 (br. s, 2H), 5.35 (m, 1H), 5.70 (m, 1H), 9.59 (d, J=3.5 Hz, 1H) IR spectrum (KBr): 1725 cm-1

Provenance & Evidence