Microwave‐assisted Chemistry of Carbohydrates

Microwave-assisted hydrolysis of nitroglycerin (NG) under mild alkaline conditions: New insight into the degradation pathway

“…The presence of large number of ions (Na + ,OH À , and CO À 3 2 in the present system) is also reported to enhance hydrolysis by the superheating effect they cause in the microwave-assisted reaction (Baghurst and Mingos, 1992;Mingos and Baghurst, 1997). Indeed microwave has been recently used to enhance many chemical reactions including the hydrolysis of amides and proteins (Gedye et al, 1986;Chen et al, 1987), sucrose (Chen et al, 1990), starch (Yu et al, 1996;Corsano et al, 2004), and the time required to carry out the well known Williamson ether synthesis from several hours to as little as one minute (Mingos and Baghurst, 1997).…”

Conversion of Carbohydrates Under Microwave Heating

“…Several methods and protocols have been reported for the MW-assisted regioselective protection of hydroxyls, especially in mono-and disaccharides (Corsaro, 2004). They include mainly acetal formation with aldehydes and acylation with acetic anhydride or an acyl chloride.…”

“…Even if widely employed in common organic chemistry, microwaves find however fewer applications in carbohydrate chemistry (Corsaro, 2004;Cioffi, 2008;Richel, 2011a). This fact, usually associated to a high number of unwanted and uncontrolled typical sugars reactions such as carbonisation or browning processes, has been overcame by the design of novel sophisticated microwave reactors.…”

“…Using citral dimethylacetal, transacetalation provides, under Cleavage of the glycosidic linkage is denoted and leads also to the formation of unwanted side-products (17-26% yield after 2 to 10 min of MW exposure) (Salanski, 1998). For deprotection processes, microwave heating is decisive and powerful, as a drastic diminution of reaction times is observed without affecting the initial anomeric configuration (Corsaro, 2004). An efficient and green protocol concerns the use of neutral alumina to ensure the regioselective depivaloylation of a set of carbohydrate derivatives (Fig 8a).…”

Sucrose chemistry: Fast and Efficient Microwave-assisted Protocols for the Generation of Sucrose-Containing Monomer Libraries

“…These monomers could be converted into pure linear polymers, avoiding the formation of mixtures of di-and higher substituted unsaturated esters, which results in cross-linked polymers (Chen and Park, 2000). Saccharide containing synthetic polymers have attracted great attention because of their potential as biotechnological, pharmacological, and medical materials (Varma et al, 2004 Microwave-enhanced synthesis has been extended to almost all areas of chemistry (Lidstrom et al, 2001) with the exception of carbohydrate chemistry which has suffered a certain delay, as is testified by the limited number of applications (Corsaro et al, 2004;Soderberg et al, 2001). In particular, it had previously not been applied to sucrose chemistry, and the general opinion is that the method is hampered by competitive degradation of sucrose because of its thermal instability (Queneau et al, 2007).…”