Figure 1: Carbon–carbon bonds formation from olefins.

(a) Alkyl organometallic reagents used in cross-coupling reactions. Alkylboron reagents^47,48,49 are usually made through alkene hydroboration. Grignard^50,51, organolithium^52,53 and alkylznic reagents^42,54 are generally obtained through insertion of metals into alkyl halides. However, an often ignored problem is that most terminal alkyl halides are converted from olefins⁵⁵. (b) Comparison of reductive olefin hydrocarbonation reaction with transition metal-catalyzed Kumada-coupling reaction. From a viewpoint of synthetic chemistry, the combination of olefins with silanes could be recognized as equivalent to alkyl organometallic reagents. 9-BBN=9-borabicyclo[3.3.l]nonane.