Aliphatic organolithiums by fluorine–lithium exchange: n-octyllithium

✍ Scribed by Miguel Yus; Raquel P Herrera; Albert Guijarro

• Book ID: 104253868
• Publisher: Elsevier Science
• Year: 2003
• Tongue: French
• Weight: 72 KB
• Volume: 44
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(03)01194-8

✦ Synopsis

The reaction of 1-fluorooctane (1) with an excess of lithium powder (4-10 equiv.) and DTBB (2-4 equiv.) in THP at 0°C for 5 min gives a solution of the corresponding 1-octyllithium (2), which reacts then with different electrophiles at 0°C (D 2 O, MeSiCl, Bu t CHO, Et 2 CO), or -78°C [ClCO 2 Me, (PhCH 2 S) 2 ] or -40°C (CO 2 ) to room temperature to give, after hydrolysis, the expected products (3). The same process applied to 2-fluorooctane gives mainly octane as reaction product, independently on the electrophile used, resulting from a proton abstraction by 2-lithiooctane formed from the reaction medium before addition of the electrophilic reagent.