On the use of mixtures of organotin species for catalytic enantioselective ketone allylation—a detective story†
Abstract
In the presence of enantiopure MTBH2
(O)Me takes place with impure Sn(CH2CH
CH2)4
(prepared from
CH2)4 yields material of only 35–50% ee. The origin of these effects is the presence of small amounts of the compounds, EtSn(CH2CH
CH2)3, ClSn(CH2CH
CH2)3 ClSnEt(CH2CH
CH2)2 in the
CH2)2 affords crystallographically characterised Sn4(μ3-O)(μ2-Cl)2Cl2Et4(CH2CH
CH2)4. Reaction of this latter compound with MTBH2 leads to the most potent