2- propenoates

The 3-formyl group of 8-substituted 3-formyl-2-hydroxy-4//-pyrido[l,2-n]pyrimidin-4-one was reacted with (cyanomethyl)- and (terr-butoxycarbo-nylmethylene)triphenylphosphorane in THF, and with 5-aminotetrazole in boiling MeOH for 9h to yield ( )-3-propenenitrile, terr-butyl ( )-3-propenoate and 3-[(2//-tetrazol-5-yl)imino]methyl derivatives, respectively (OlMIPl). 

The reaction with HI at 25 °C gave the iodo analogue. However, if the reaction was run at a higher temperature, a mixture of 2-iodo-3-propenoic acid and 2-iodo-2-propenoic acid was formed [252],... 

Cinnamic acids are fra/ty-phenyl-3-propenoic acids differing in their ring substitution, Fig. (2). 

Answer XlV-d is an o,p-unsaturatcd ester (ethyl 2-n-propyl-3-cydobu ty 1-3- propenoate). 

The intramolecular Diels-Alder reactions involving boryl-3-propenoic acid derivatives has been addressed to. So, heating the trienylamide (7) at 80°C in toluene for 15 hours led to a 1/3 mixture of the cycloadducts (8) and (8 ) isolated in 72 % yield (figure 6) l7. The trienylamide (9) could not be isolated since the IMDA occured at the temperature of the coupling step, i,e below 0°C in ether for 30 minutes. This very fast cyclisation led to a 85/15 mixture of cycloadducts (10) and (10 ) having respectively a cis and trans junction in the bicyclic structure. The cis bicyclic structure (10) results from an endo approach of the diene and the dienophile. This is in agreement with literature data l8. 

Photocycloaddition of chiral crystals of the optically pure (S)-(-l-) or ( )-(—) monomer ethyl 2-cyano-3-[p-sec-butyl-3 -( )-propenoate]-phenyl-(E)-propenoate (237), provided photodimers and polymers with quantitative diastereomeric yields from ]2tc -l- 2tc topochemical photocycloaddition [183] (Scheme 37). 

C4H6O2 96-33-3 Propenoic acid methyl ester see Methyl propenoate... 

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