3.3.5- Trimethyl-2-pyrrolidinone

Decomposition of l-methyl-2-pyrrolidinone (67) was studied by vapor-phase photolysis (72JA8281). Irradiation (Hg sensitized) led, in addition to extensive polymer formation, to the following products carbon monoxide (31%), ethene (24%), water (24%), l,3,5-trimethyl-hexahydro-l,3,5-triazine (8%), 1-methylazetidine (6%), 1-methylpyrrole, and methane (<1%). The mechanism of formation of most of these products involves... 

Among all the quatemized chitosans described into literature, W,W,W-trimethyl chitosan chloride (TMC) is the most widely applied for gene therapy applications [28, 33, 34]. The quatemization maintained and improved the muco-adhesive properties of chitosan, depending on the quatemization degree, which makes this chitosan derivative an ideal candidate for gene delivery [23]. Typically, TMC can be synthesized by reaction of chitosan with methyl iodide in the presence of sodium hydroxide into A-methyl-2-pyrrolidinone at 60 °C. In a second step, the iodide ion is substituted by chloride by an ion exchange process [34] (Fig. 2). 

Another radical addition reaction pertinent to this section has been reported. In this case, however, the radial reaction was initiated photochemically. Photolysis of 2-aminopropane in the presence of ethyl crotonate led to an amino-ester (3.44), which spontaneously cyclized to 4,5,5-trimethyl-2-pyrrolidinone, 3.45.2 Aqueous acid hydrolysis liberated 3,4-dimethyl-4-aminopentanoic acid, 3.46. 

Pawloswski et al. described the s5mthesis of acetoacetoxypropyl cellulose (AAPC), formed by the acetoacetylation of hydroxypropyl cellulose using a diketene/acetone adduct (2,2,6-trimethyl-4-H-l,3-dioxin-4-one) in A/-methyl-2-pyrrolidinone (NMP) at elevated temperature. The authors showed that as with APC, AAPC also forms both thermotropic and lyotropic liquid-crystalline phases. It is noteworthy to mention that the nematic to isotropic transition occurs at 174 °C and thin films of cholesteric thermotropic AAPC show green reflection colors (Pawlowski et al. 1986, 1987). 

N-Trimethyl chitosan chloride (TMC) with introduced quaternary amino groups on the chitosan chain has been synthesized using iodomethane in an alkaline solution of N-methyl pyrrolidinone (NMP). Quaternization is based on the nucleophilic alkylation of the primary amino group at the C-2 position of chitosan [41]. TMC... 

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