diisobutylaluminium hydride; trifluoroacetic acid 1) -78 deg C, Et2O, 1 h, then 6 h, room temperature, 2) -78 deg C, warming up to room temperature over 1 h, then 1 h, room temperature; Yield given. Multistep reaction. Yields of byproduct given. Title compound not separated from byproducts;

diisobutylaluminium hydride; trifluoroacetic acid 1) -78 deg C, Et2O, 1 h, then 6 h, room temperature, 2) -78 deg C, warming up to room temperature over 1 h, then 1 h, room temperature; Yield given. Multistep reaction. Yields of byproduct given. Title compound not separated from byproducts;