Dissolving metal cleavage ethers

The central bond in 1 undergoes reductive cleavage with dissolving metals. For instance, reaction of la and lo with lithium 4,4 -di- -butylbiphenyl in dimethyl ether yields poorly soluble and incompletely characterized organometallic derivatives in moderate yields, presumably the corresponding l,3-dilithiobicylo[l.l.l]pentanes (64)95 (equation 24). The... 

On a related front, the reactions of carbonyl compounds with metaliated derivatives of 2-methylthia-zoline furnish adducts (85). Although the initial nucleophilic addition occurs smoothly with a wide variety of aldehydes and ketones, the intermediate P-hydroxythiazolines (85) suffer thermal reversion upon attempted purification by distillation. Moreover, attempted cleavage of the corresponding P-hydroxythia-zolidines, which are readily produced from (85) upon dissolving metal reduction (Al-Hg), leads to the formation of p-hydroxy aldehydes only in simple systems numerous complications arising from dimerization, dehydration and retroaldol processes of the products usually intervene. Consequently it is necessary to protect the initial 1,2-adducts (85 = H) as the corresponding 0-methoxymethyl ether... 

Epoxide cleavage which follows upon dissolving metal reduction of proximal cyclopropane rings makes possible the ready synthesis of functionalized strained ring compds. otherwise inaccessible. - E An ethereal soln. of 7,7-dimethyl-6,8-diphenyl-3-oxatetracyclo[3.3.0.02,4.06,8]octane added to anhydrous NH3 containing Li-wire, and stirred 1 hr. at -33° 5,5-dimethyl-eu /o-4,6-diphenyltri-cyclo[4.1.0.03,7]heptan-2-exo-ol. Y 90%. F. e. s. L. A. Paquette et al., J. Org. Chem. 39, 467 (1974). 

---