The most stable conformation of trqans-l,2-cyclohexanediol is the chair in which both hydroxy groups are equatorial, (a)

Question:

The most stable conformation of trqans-l,2-cyclohexanediol is the chair in which both hydroxy groups are equatorial,
(a) Draw the structure or, better yet, make a model of the compound in this conformation,
(b) Reaction of this diol with the chlorosilane R3SiCl, R = (CH3)2CH (iso-propyl), gives the corresponding disilyl ether shown in the margin. Remarkably, this transformation causes the chair to flip, giving a conformation where both silyl ether groups are in axial positions. Explain this observation by means of either structural drawings or models.