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How do you make primary alcohol from an alkene?

Answer 1

Hydroboration are the typical means to make a primary alcohol from an olefin.

When an olefin is treated with aqueous acid, #H^+# adds as an electrophile. And so the most stable resultant carbocation is the one with most substitution. Propylene would give predominately #"2-propanol"# on acidic hydration.

On the other hand, when say #"2-methylpropene"# is treated with borane in THF, the hydrogen adds as an hydride:

#H_2C=C(CH_3)CH_3 +B""^2H_3 rarr (""^2H_2BCH_2C-C""^2H(CH_3)CH_3)# (I labelled the borane so you could see how the hydrogens add. The #B-H# bond adds across the olefin in a concerted mechanism.)

The electrophile in this instance is the boron center that lacks electrons.

Oxidative work up gives the primary alcohol #HO-CH_2C-CH(CH_3)CH_3# and an inorganic borate.

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Answer 2

Addison Armstrong

Primary alcohols can be synthesized from alkenes through a process called hydroboration-oxidation. This involves the addition of boron to the alkene using boron trifluoride (BF3) followed by treatment with sodium hydroxide (NaOH) and hydrogen peroxide (H2O2).

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.