NEW COMPOUNDS OF UREA-FORMALDEHYDE CONDENSATION PRODUCTS
نویسندگان
چکیده
منابع مشابه
New Mechanism Proposed for the Base-Catalyzed Urea–Formaldehyde Condensation Reactions: A Theoretical Study
Base-catalyzed urea–formaldehyde condensation reactions were investigated by using a quantum chemistry method. It was found that monomethylolurea or N,N’-dimethylolurea can produce the methyleneurea intermediate (–HN–CO–N=CH2) with the catalysis of base. The E1cb (unimolecular elimination of conjugate base) mechanism was identified for the formation of such an intermediate. The potential energy...
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A definition of the term " l i f e " , if understood as one element in a supposed class of extraterrestrial and prebiological phenomena, is shown to be logically impossible because life is the sole known element of that class. Instead, the properties of the class of "b io ids" , defined as the class of " open systems which can exist in several steady states" (DECKER and SPEIDEL, Chemiedozentent...
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ژورنال
عنوان ژورنال: Bulletin of the Chemical Society of Japan
سال: 1936
ISSN: 0009-2673,1348-0634
DOI: 10.1246/bcsj.11.248