Evans experimental confirmation

Faraday, to whom Schonbein s first communication was sent as a letter, made further experiments. In his second paper he gives a history of earlier work previously unknown to him and Schonbein. As a result of experiments Faraday concluded that the peculiar condition of iron is due to the protection of the iron by a coat of oxide. .. so thin as not to be sensible , or, alternatively that the superficial particles of the metal are in such relation to the oxygen of the electrolyte as to be equivalent to an oxidation.. . having thus their affinity for oxygen satisfied , which would cover several theories proposed later. The oxide-film theory was experimentally confirmed by U. R. Evans. ... 

The necessity for a co-catalyst with BF3 was subsequently confirmed rigorously by Evans and Meadows [8-10] by means of an all-glass vacuum apparatus which established a characteristic style of experimentation which I adopted and adapted. They showed that under rigorously anhydrous conditions isobutene and BF3 could be mixed without the isobutene polymerising, and that the addition of water did initiate a polymerisation. Fairbrother and Frith [11] reported very briefly that the polymerisation of isobutene by (Ta-Nb)F5 required a co-catalyst - without stating which one they used. 

Makino and others carried out a computational study on the Evans aldol reaction of dimethylborinate 12BMe2 with acetaldehyde7 (Scheme 2.1h). The AMI semiempirical calculations indicate that six-membered chairlike transition state A, which would lead to formation of the major syn-isomer, is more stable than B by 3.0kcal/mol, providing a theoretical confirmation of the experimental observations. 

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