Oxaspiro undecane

Pentaerythritol can be converted to the biscycHc formal, 2,4,8,10-tetra-oxaspiro[5,5]undecane [126-54-5] ... 

FIGURE 27 Release of cyclobenzaprine hydrochloride (CBP) at 37 C and pH 7.4 from devices made at different injection-molding temperatures. Polymer prepared from 3,9-bis(ethylidene-2,4,8,10-tetra-oxaspiro[5,5]undecane) and a 25 75 mole ratio of trans-cyclohexane dimethanol and 1,6-hexanediol and contained 3 wt% phthalic anhydride and 7.5 wt% cyclobenzaprine hydrochloride (CBP). 

M. A. Frolov, I. V. Molyavko, A. I. Spivak, D. L. Rakhmankulov, V. R. Rakhmatullin, and N. A. Romanov. Lubricant for friction pairs working under heavy loads—contains mineral oil and additive in form of 2,4,8,10-tetra-oxaspiro-(5,5)-undecane, to improve anti-wear and anti-scratch properties. Patent SU 1817788-A, 1993. 

In order to testify to the versatility of the Reformatsky reaction, two examples of three-component processes are presented the synthesis of 3-aryl-4,4-dimethyl-2-oxaspiro[5.5] undecane-1,5-diones 1485 (equation 12), and the coupling of two molecules of methyl 2-bromo-2-methyl propanoate (If) with an oxoaryl acetaldehyde 15 to afford 3a-aryl-3,3,6,6-tetramethyl-tetrahydrofuro[3,2-b]furan-2,5-dione 1686 (equation 13). 

Spirocyclic 4-substituted tetrahydropyrans are readily obtained through the Prins reaction involving cyclic ketones, homoallylic alcohols and MeS03H <02H(58)659>. The cationic species generated when alkyne-Co complexes derived from 8-valerolactone are treated with SnCl4 undergo a double cyclisation to yield the oxaspiro[5.5]undecane <02T2755>. 

Among the systems with chemical different donor and acceptor molecules, the photocopolymerization between maleic anhydride (MSA), which functions as an acceptor, and electron-rich monomers has been widely investigated. As donor monomers such compounds as styrene (Sty) [19-29], cyclohexene [30], N-vinylcarbazole [31], 2-vinyl naphthalene [32], vinyl acetate [33], 2.4.8.10-tetra-oxaspiro[5.5]undecan [34] and phenyl glycidyl ether (2,3-epoxypropyl phenyl ether, PGE) [35] have been used. In all the above cases, using high concentrations of both monomers, the absorption of the CT has been obtained in various solvents. Thus, with spectroscopic methods the complex formation constant Kct can be calculated (e.g., MSA-cyclohexene Kcl = 0.0681 mol -1 [33], MSA-tetrahydrofuran Kct = 0.331 mol-1 [36]), and a selective excitation of the CT is possible in many cases. 

Ethylene glycol (0.022 mole) 3,9-Bis(7-carboxymethoxy-heptyl)-2,4,8,I0-tetra-oxaspiro[5,5]undecane (0.02 mole) 210-295 11 5700 d... 

Cl4H24O2, trans-9-t-Butyl-l-oxaspiro[5,5]undecan-2-one, 41B, 373 Cl4H24O4, trans-anti-trans-4,5 9,1O-Bis(cyclohexano)- ,3,6,8-tetra-oxecane, 45B, 334... 

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