Hydrogen propene oxidation

Cyclization of the iodoaromatic precursor 215 via Heck methodology to afford the l//-3-benzazepine-2-carboxylic ester 216 has been described (Scheme 29) <1997J(P1)447>. The ester 216 was then converted to the conforma-tionally restricted phenylalanine analogue 217 by hydrogenation and ester hydrolysis with concomitant BOC group removal under acidic conditions (HC1), followed by reaction with propene oxide. 

The propene oxidation process is globally conducted on a 5 million t/a scale. A new gas-phase oxidation process of propene to propene oxide using hydrogen peroxide would save the use of solvents and is expected to have higher selectivity. 

The industrial process for propene oxide manufacture is commonly referred to as the HPPO (hydrogen peroxide propene oxide) process. EniChem set up a prototype plant in 2002 [150]. BASF/Dow Chemicals and Degussa, in turn, have the construction of commercial plants already in progress or at the planning stage [151]. 

The integration of propene oxide and hydrogen peroxide processes appears, from a short-term perspective, a more realistic approach than in situ generation. It is also favored by the location of both facilities at the same chemical site. Basically, process integration envisages a simplification of H2O2 recovery that can even... 

The main products of the gas-phase photolysis at 300 °K, with nitric oxide added, are hydrogen, propene, ethylene and pentenes. Other important products are ethane, butenes, methane, propane, butane and acetylene. A reaction scheme that accounts for most of the products of the nitric oxide-inhibited photolysis is as follows... 

---