Which of the following reactions can be used to prepare diborane ?
I. `BF_(3) +LiAlH_(4)overset("Ether")to`
II. `BF_(3) +NaHoverset(450 K) to `
III. `Na_(2) B_(4)O_(7) +H_(2)O to`
IV. `NaBH_(4) +l_(2) to `

Options

A. I, II, III
B. II, III only
C. III, IV only
D. I, II, IV

Answer

D

Explanation

Following reactions are used for the preparation of diborane:
(I) `4BF_(3) +3LiAlH_(4) overset("Diethyl ether")tounderset("Diborane")(2B_(2) H_(6))+ 3LiF + 3AlF_(3)`
(II) `2 BF_(3) + 6NaH overset(450 K) underset("Diborane")(B_(2)H_(6))+6NaF` (Industrial method)
(IV) `2NaBH_(4)+I_(2) overset("DIGLYME"(MeOCH_(2) CH_(2))O_(2))to underset("Diborane")(B_(2) H_(6)) underset(("Lab method"))(+2NaI+H_(2)uarr)`
Reaction (III) is used for the preparation of boic acid i.e.
`Na_(2)B_(4) O_(7) + 7H_(2) O hArr 2 NaOH + underset("Boric acid")(4H_(3)BO_(3))`
Thus, option (d) is correct .