Polyolefins as Substrates

In the hydroformylation of nonconjugated polyolefins, the less substituted double bond reacts first. A typical substrate is fi-citronellene (dihydromyrcene). 

The hydroformylation in ethanol solutions gives, depending on the reaction temperature, either almost exclusively the aldehydes or a mixture of aldehydes and acetals with different organoleptic properties [93]. 

1) Unfortunately, no other reactions conditions (catalyst, solvent, time) are detailed in the review. Probably an unmodified Co catalyst was used. 

Citronellal is used in cheap perfumes and for the perfuming of cigarettes. The homolog aldehyde could be obtained under the same conditions in a yield of 63%. 

For the double hydroformylation, no chiral descriptors have been given in the patent. 

---

Cyclic Polyolefins (GPO) and Gycloolefin Copolymers (GOG). Japanese and European companies are developing amorphous cycHc polyolefins as substrate materials for optical data storage (213—217). The materials are based on dicyclopentadiene and/or tetracyclododecene (10), where R = H, alkyl, or COOCH. Products are formed by Ziegler-Natta polymerization with addition of ethylene or propylene (11) or so-called metathesis polymerization and hydrogenation (12), (101,216). These products may stiU contain about 10% of the dicycHc stmcture (216). 

---