This is done by a net addition (across the entire double bond) of … Because the carbon-carbon π bond is relatively weak, it is quite reactive and can be easily broken and reagents can be added to carbon. That is, the mechanism is “concerted” (Those dashed lines below represent “partial bonds”). The hydroboration oxidation reaction is an organic chemical reaction which is employed for the conversion of alkenes into alcohols that are neutral. The general form of the hydroboration of alkenes mechanism is as follows: First step is the attack of the alkene on BH 3, which then forms a four membered ring intermediate of partial bonds. In this first step the addittion of the borane to the alkene is initiated and prceeds as a concerted reaction because bond breaking and bond formation occurs at the same time. THF (tetrahydrofuran) is the solvent that is used to stabilize the dimer of BH 3 which is a flammable, toxic, and explosive gas: It is a few-steps transformation that starts from the addition of borane (BH 3) to the alkene. Hydroboration Of Alkenes: A Proposed Mechanism Instead of proceeding in multiple steps, as do reactions in the carbocation and 3 membered ring pathway, the hydroboration reaction occurs all at once. Catalytic Hydrogenation of Alkenes The double bond of an alkene consists of a sigma (σ) bond and a pi (π) bond. bondof the nucleophile. It is because of this intermediate that hydroboration forms the anti-Markovnikov product. Hydroboration-Oxidation of Alkenes. This is called hydroboration and it is an electrophilic addition to the alkene. This part consists of the vacant 2p orbital of the boron electrophile pairing with the electron pair of the ? Reagents are added through the formation of single bonds to carbon in an addition reaction. Hydroboration-Oxidation is a two step pathway used to produce alcohols. This is done via a two-step process which includes a hydroboration step and an oxidation step. Part #1: Hydroboration of the alkene. The reaction proceeds in an Anti-Markovnikov manner, where the hydrogen (from BH 3 or BHR 2) attaches to the more substituted carbon and the boron attaches to the least substituted carbon in the alkene bouble bond.