Propene oxide synthesis

Schreiber found that the monoalkylation of the lithium enolate of cyclonona-none with propene oxide could be cleanly effected by addition of AlMe3 to give the y-hydroxy ketone 145, a key intermediate for the synthesis of recifeiolide [69a]. 

Current commercial production of methyloxirane (propene oxide), used extensively in the production of polyurethanes, is usually based on a chloro-hydrin process. However, the direct gas-phase synthesis of methyloxirane... 

Functionalization of hydrocarbons from petroleum sources is mainly concerned with the introduction of oxygen into the hydrocarbon molecule. In general, two ways are open to achieve oxygen functionalization oxidation and carbonylation. Oxidation is commonly encountered in the synthesis of aromatic acids, acrolein, maleic anhydride, ethene oxide, propene oxide, and acetaldehyde. Hydroformylation (CO/H2) (older literature and the technical literature refer to the oxo reaction) is employed for the large-scale preparation of butanol, 2-ethylhexanol, and detergent alcohols. The main use of 2-ethylhexanol is in phthalate esters which are softeners in PVC. The catalysts applied are based on cobalt and rhodium. (For a general review see ref. 3.)... 

The same differential behavior can be observed with amine nucleophiles. For example, calcium triflate promotes the aminolysis of propene oxide 84 with benzylamine to give 1-(A -benzyl)amino-2-propanol 85, the result of attack at the less substituted site <03T2435>, and which is also seen in the solventless reaction of epoxides with heterocyclic amines under the catalysis of ytterbium(III) triflate <03SC2989>. Conversely, zinc chloride directs the attack of aniline on styrene oxide 34 at the more substituted carbon center <03TL6026>. A ruthenium catalyst in the presence of tin chloride also results in an SNl-type substitution behavior with aniline derivatives (e.g., 88), but further provides for subsequent cyclization of the intermediate amino alcohol, thus representing an interesting synthesis of 2-substituted indoles (e.g., 89) <03TL2975>. 

Synthesis of Propene Oxide A Successful Example of Sustainable Industrial Chemistry... 

Synthesis of Propene Oxide A Successfui Exampie of Sustainabie industriai Chemistry Table 6.6 Results over various catalytic systems reported in the literature... 

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