BF3 boron trifluoride

Examples of neutral Lewis acids are halides of group 3A elements, such as BF3. Boron trifluoride, a colorless gas, is an excellent Lewis acid because the boron atom in the trigonal planar BF3 molecule is surrounded by only six valence electrons (Figure 15.12). The boron atom uses three sp2 hybrid orbitals to bond to the three F atoms and has a vacant 2p valence orbital that can accept a share in a pair of electrons from a Lewis base, such as NH3. The Lewis acid and base sites are evident in electrostatic potential maps, which show the electron poor B atom (blue) and the electron rich N atom (red). In the product, called an acid-base adduct, the boron atom has acquired a stable octet of electrons. 

Predict the shapes of the following molecules H2S (hydrogen sulfide), CaCl2 (calcium chloride), CH4 (methane), BF3 (boron trifluoride), and KBr (potassium bromide). 

In Scheme 1.3, hexanal on reaction with 1,3-propanedithiol gives the 1,3-dithiane derivative 1.8. A strong base such as u-butyllithium abstracts the proton to give the corresponding 2-lithio-1,3-dithiane 1.9, which reacts with 1-bromopentane to give alkylated product 1.10. Treatment of 1.10 with FIgO and BF3 (boron trifluoride) in aqueous THF (tetrahydrofuran) yields the dipentyl ketone (the corey-seebach reaction ). Thus, dithianyllithium (2-lithio-1,3-dithiane) 1.9 is an acyl anion synthetic equivalent. 

BF3 boron trifluoride 7637-07-2 3.768E-I-09 26.510 2685 N2H4 hydrazine 302-01-2 3.480E+09 21.080... 

BF3 BORON TRIFLUORIDE 22.487 1.1814E-01 -8.7099E-05 2.2344E-08 1.2182E-13 100 1500 gas... 

Next we will look at the BF3 (boron trifluoride) molecule, known to have planar geometry based on VSEPR. Considering only the valence electrons, the orbital diagram of... 

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