CH2=CHCHO

Acrolein (CH2=CHCHO) can be substituted for formaldehyde and acetaldehyde in the above reaction to give similar results, but the proportion of (3) is higher than when acetaldehyde and formaldehyde are fed separately. Acrolein may be formed as one of the first steps to pyridine (1) and P-picoline (3) formation. There are many variations on the vapor-phase synthesis of pyridine itself. These variations are the subject of many patents in the field. 

Consider the bonding in CH2=CHCHO. (a) Draw the most important Lewis structure. Include all nonzero formal charges, (b) Identify the composition of the bonds and the hybridization of each lone pair—for example, by writing o(H ls,C2s/ 2). 

Acrolein Allyl aldehyde, propenal) CH2 CHCHO -26 278 2.8-31.0 0.8 1.9 53 Colourless/yellow liquid Pungent unpleasant odour Water soluble Irritant Can polymerize exothermically with strong alkalis, heat or light Can form peroxides... 

The early ammoxidation plants were a two-step design. Propylene was catalytically oxidized to acrolein (CH2=CHCHO). The acrolein was then reacted with ammonia and air at high temperature to give acrylonitrile. The one-step process has replaced most of this hardware. 

Results for the cell with a Cu—molybdena—YSZ anode, shown in Figure 16b, were very different. Unlike ceria, which is a nonselective oxidation catalyst, molybdena is a selective catalyst for the partial oxidation of propylene to acrolein (CH2=CHCHO) and is used commercially for this process. The primary product at low conversion over the Cu— molybdena—YSZ electrode was acrolein, produced according to the reaction... 

Scheme 42. Reaction conditions i, Mg-THF ii, CH2=CHCHO iii, Mn02 iv, 1-nitropentane V, H2-Pd/C, Na2S04 vi, H3O + vii, NaBCNHj.

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