When a solution containing (C5Me5)2Os2Br4 and LiAlH4 is stirred at low temperature in di...

When a solution containing (C₅Me₅)₂Os₂Br₄ and LiAlH₄ is stirred at low temperature in diethyl ether, followed by addition of a small amount of ethanol, a white product is formed that can be isolated by sublimation. Analysis of the white product, an

18-lectron complex, provided the following information: Elemental analysis: 36.6 % C, 6.07 % H ¹H NMR: δ 2.02 (s, relative area- ), –11.00 (s, relative area-1) ¹³C NMR: δ 2.02 (s), 94.2 (s) IR: the region where Os—H stretches most likely occur is shown.

Propose the structure of the product, and account for as much of the data as possible. (See C. L. Gross, G. S. Girolami, rganometallics , 2007 , 26 , 160.)