
TY  - JOUR
A1  - Bourke, David G. 
A1  - Collins, David J. 
A1  - Bannister, Jonathan D. 
A1  - Doherty, Carolyn L. 
A1  - Fallon, Gary D. 
A1  - Lim, Yvette 
A1  - Ting, Tina Lim Phaik 
A1  - Ward, Brent R. 
T1  - Conversion of 12&#945;-Hydroxyandrosta-1,4-diene-3,17-dione into a Derivative of 12-Oxoestradiol: a Novel C9&#8211;C 10 Cleavage Reaction
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1998
VL  - 51
IS  - 5
SP  - 353
EP  - 360
KW  - 
UR  - https://doi.org/10.1071/C97147 
N2  - Reaction of 12&#945;-hydroxyandrosta-1,4-diene-3,17-dione (1) with 2,2-dimethylpropane-1,3-diol in the presence of pyridinium p-toluenesulfonate gave the corresponding 17,17-cyclic acetal (2). Oxidation of (2) with chromium trioxide in pyridine gave 5&#8242;,5&#8242;-dimethylspiro&#91;androsta-1,4-diene-17,2&#8242;-&#91;1,3&#93;dioxan&#93;-3,12-dione (5) which underwent base-catalysed cleavage to give the novel 9,10-secosteroid (8). Selective reduction of (1) at C17 gave 12&#945;,17&#946;-dihydroxyandrosta-1,4-dien-3-one (9a); selective protection of this at C17, followed by oxidation with chromium trioxide in pyridine gave 17&#946;-(t-butyldimethylsilyloxy)androsta- 1,4-diene-3,12-dione (10), regioselectively protected as the 12,12-ethylenedioxy acetal (12). Treatment of (12) with lithium in tetrahydrofuran in the presence of biphenyl and diphenylmethane effected reductive aromatization of ring A to give a mixture of 17&#946;-(t-butyldimethylsilyloxy)-12,12-ethylenedioxyestra-1,3,5(10)-trien-3-ol (15a) and the corresponding 17-alcohol (15b). Conversion of (15a) into the corresponding 3-benzyl ether (14a), followed by acid-catalysed hydrolysis gave 12-oxoestradiol 3-benzyl ether (13). 
ER  -

