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Download (4Mb) - Etheses - Saurashtra University

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Part-IIImpact of Microwave…glycine methyl esters in the presence of sodium cynoborohydride (NaBH 3 CN). Goodyields and short reaction times are the main aspects of these procedures 8 .H 3 NCl -OO1. R 1 CHO, TEA, MeOH, MWI2. NaBH 3 CN, MWIHNR 1 1OOR 1 = 2,6-Cl Ph, 2,6-methyl Ph, 3,5 dimethyl-4-hydroxy Ph, 4-ClPh, 3-NO 2 Ph etc.Rottger et al., 9 have successfully developed a general method for the microwave-inducedN-arylation of amino acids in water providing moderate to high yields and less than 6%racemization. A diverse set of amino acids 2 (20 derivatives) and differently substitutedaryl bromides were fully reacted after 40 min of microwave radiation. In addition, variousamino acid esters could be N-arylated with simultaneous deprotection, generating the freeacid as product.RNH 2. HXBrCOOR 1R 1 = CH 3 , Et, t-Bu, allylHX= HCl, HOTs+CuI, KI, K 2 CO 3MWIRCOOHNH2Amino acid ester= L-Leu,L-Phe, L-Lcu etcR= H, CH 2 PhWipf et al., 10 have developed an expeditious divergent multi-component reaction method,combining the advantages of microwave reaction acceleration and combinatorialtechnologies with a libraries-from-libraries concept to prepare 20 allylic amides and C-cyclopropylalkylamides and create an expanded 100-member library as in scheme-1. Thelibrary building blocks consisted of 3 alkynes, 7 phosphinoylimines, 10 acid chlorides, 6carbamoyl chlorides, and 9 sulfonyl chlorides (Scheme-1).276

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