Epoxides cyclic

MCPBA epoxidations cyclic alkenes and methylenecycloalkanes having Erecting groups... 

MCPBA epoxidations cyclic alkenes, methylenecycloalkanes and unsaturated macrocycUc lactones... 

MCPBA epoxidations cyclic alkenes and methylenecycloalkanes having directing groups 3.122 J MCPBA epoxidations acyclic alkenes having directing groups... 

Like the epoxides, cyclic sulfates can be opened with inversion of configuration by nucleophilic attack at a carbon center (Scheme 40). The cyclic sulfates are easily prepared by oxidation of the corresponding sulfites using stoichiometric amounts of NaI04 and catalytic quantities of RUCI3.3H2O [117]. Simple filtration... 

Virtually all known types of cationically polymerizable monomers are polymerized using onium salt photoinitiators. Included among these monomers are epoxides, cyclic ethers, mono and polyfunc-tional vinyl compounds, spiroesters, spirocarbonates and cyclic... 

As an alternative functional group to an epoxide, cyclic sulfates and sulfites have also been used as intermediates to prepare the taxol side chain. Thus, asymmetric dihydroxylation of cis methyl cinnamate using AD-mix (3 gave the diol 7.2.12, which was converted to the cyclic sulfate... 

When (1 R,2R)-2-bromocyclohexanol is treated with a strong base, an epoxide (cyclic ether) is formed. Suggest a mechanism for formation of the epoxide ... 

You might also recall from Section 12.7 that epoxides, cyclic ethers with a three-memhered ring, are unusually reactive in Sn2 processes because of angle strain. Methylenecyclohexane oxide, for instance, undergoes a base-induced Sn2 ring-opening on treatment with hydroxide ion at 100 °C. 

There are a number of heterocyclic monomers, for example, epoxides, cyclic sulfides, lactones and lactides, lactams, cyclic carbonates, and cydosUoxanes, which can be polymerized by ring-opening reactions many of them can he polymerized by an anionic as well as by a cationic mechanism. They cannot all be covered here, but there are a number of monographs and reviews on this subject [181-185]. 

The ability of the methanotrophs to oxidize methane has been recognized for over 80 years, but the detailed studies of their metabolism started in the 1970s [16]. The oxygenation initiates the metabolic pathway that supplies the total carbons and energy required by the methanotrophs. In the methanotrophs, the enzyme MMO can also oxidize a variety of other alkanes, alkenes, ethers, and alicyclic, aromatic, and heterocyclic compounds as substrates to provide corresponding primary, secondary, or tertiary alcohols, epoxides, cyclic alcohols, and phenols, although these substrates do not participate in the growth of the bacteria [17]. 

Suslick et al found that the porphyrinic MOF, PIZA-3, is capable to heterogeneously oxidize a range of linear and cyclic alkanes and epoxidize cyclic alkenes. The oxidation performance is moderate, which is similar to the homogeneous or heterogeneous Mffi Lporphyrin catalysts. Since PIZA-3 did not have shape-selective property in the reaction, the authors concluded that the catalysis occurred on the exterior surface instead of inside the pores. Their hypothesis was proved by subsequent control experiment. They added the bases that are too peripherally bulky to... 

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