Three-Membered Ring Systems

Ethoxylation of Phenols Catalyzed by Metal‐Free Lewis Pairs: Living/Controlled Polymerization in a Slow‐Initiation Mode†

“…Phenolysis of epoxide, i.e ., a “1 + 1” type ring‐opening reaction between phenol and epoxide, represents an important class of organic reactions for the synthesis of, e.g ., β ‐substituted alcohols. [ 47‐48 ] In this work, the alterable rates of the initiation and propagation reactions of the ROP indicate that it may be possible for phenol to react with an equal molar amount of epoxide, though added in a large excess, under mild conditions. Therefore, we have explored for optimized conditions that the reaction ceases or significantly slows down after the completion of the initiation stage by varying the organobase, molar ratio of organobase and Et 3 B, solvent, and reaction temperature (Table 3).…”

β-Hydroxy sulfides and their syntheses

“…The considerable ring strain present in epoxides makes them highly susceptible to nucleophilic attack and makes them versatile starting materials for the synthesis of various derivatives [ 16 – 18 ]. A number of protocols have been reported to effect their selective ring opening using thiols or disulfides as nucleophiles to obtain β-hydroxy sulfides.…”

Dilithium Tetrachloromanganate an Effective Reagent for Regioselective Ring Opening of Epoxides with Grignard Reagents

“…In the presence of chiral ligands Grignard reagents and organocuprate reagents [14][15][16] readily cleave epoxide regioselectively and yields optically active alcohols having asymmetric carbon atom. Epoxides [17][18][19][20][21][22] are versatile intermediates in many reactions and natural products that reacts with numerous nucleophiles like organometallics and provides completely different products with different selectivity, it depends on the reagents and conditions used for the reaction. The attack of organometallics on carbonyl compounds gives products alcohols by nucleophilic ring opening of epoxides or by rearrangement reaction.…”