[maakii]

Hey,

I would like to know, does the adduct (CH₃)₂O->BF₃ have a formal charge separation of +ve on O and -ve on B, as O gives its electrons to B? This matter has been confusing me for a while, as I was thinking about the addition of water to carbocations, and how water gets a positive charge that way. Does the O on the dimethyl ether get a positive charge too? Thanks!

[FeLiXe]

for all of those complexes you can either write them with a formal charge and a real bond or with an arrow and no formal charge. that is just a way of drawing things. but of course you would rather choose a real bond for strong interactions and an arrow for weak interactions