Diallyl ether, cleavage

The reaction of diallyl ether with mercury(II) nitrate in dichloromethane in the presence of an alkyl carbamate proceeds with total stereoselectivity and moderate yield. Under these conditions (thermodynamic control) the reaction gave, after reductive cleavage, the more stable diequatorial alkyl 3,5-dimelhyl-4-morpholine carboxylate 1124. 

By cleavage of suitable aliphatic ethers—e.g., diallyl ether with sodium (GH2=GH—CH2)20 4- 2 Na -h- GH2=GH—CHaNa -j- GH2=GH—GH20Na... 

Cleavage of C-0 bonds has also been observed in the reactions of Pd(C6F5)Br(NCMe)2 with diallyl ether via insertion-elimination processes (Eq. 19) [57],... 

Stoichiometric experiments were conducted with the functionalized alkenes to further explore iron-substrate interactions and gauge relative coordination affinities. Several bis(imino)pyridine iron amine and ketone compounds were isolated and studied using a combination of X-ray diffraction, NMR and Mossbauer spectroscopy and established electronic structures similar to that for ( PDI)Fe(N2)2-In the absence of H2, diallyl ether and allyl ethyl ether underwent facile C-0 bond cleavage and yielded a near equimolar mixture of the corresponding iron allyl and alkoxide complexes [89]. Our group has recently published a comprehensive study on these types of reachons and discovered rare examples of C-0 bond cleavage in saturated esters [89]. 

Stoltz reported the extension of their methodology to silyl enol ether substrates (Scheme 4.18) [36]. In many cases these enolate precursors are easier to prepare compared to their enol carbonate counterpart. The addition of diallyl carbonate was necessitated to generate the enol carbonate in situ. Tetrabutylammonium difluoro-triphenylsiUcate (TBAT) was also required to activate the cleavage of the enol silane in situ at a temperature for asymmetric induction to occur. Nearly identical levels of enantioselectivity were obtained with this system. 

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