95091-93-3Relevant articles and documents
Allene C(sp2)-H Activation and Alkenylation Catalyzed by Palladium
Aouane, Fran?oise A.,Baik, Mu-Hyun,Carreira, Erick M.,Schreib, Benedikt S.,Son, Mina
supporting information, p. 21705 - 21712 (2022/01/03)
The selective transition-metal-mediated activation of C(sp2)-H bonds of allenes is a formidable challenge because of the competitive, intrinsic reactivity of cumulated double bonds. Herein, we report a Pd-catalyzed C-H alkenylation of electronically unbiased allenes, affording penta-1,2,4-triene products in up to 94% yield. A picolinamide directing group enables the formation of putative allenyl-palladacycles, which subsequently participate in a turnover-limiting Heck-type reaction with electron-deficient alkene coupling partners. This mechanistic proposal is consistent with experimental and computational investigations. Additionally, we report for the first time the use of picolinamide N,O-acetals as readily removable auxiliaries for C-H activation reactions, allowing the efficient alkenylation of allenyl carbinol derivatives. Successful removal of the directing groups without affecting the reactive penta-1,2,4-triene substructure of the products is demonstrated.
METHOD FOR PRODUCING POLYALKYLENE GLYCOL DERIVATIVE HAVING AMINO GROUP AT END
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Paragraph 0182-0188, (2016/07/05)
A method simply produces a narrowly distributed and high-purity polyalkylene glycol derivative having an amino group at an end without using a heavy metal catalyst. A method for producing a polyalkylene glycol derivative having an amino group at the end by reacting a compound represented by the general formula (V) with an alkylene oxide, then reacting a reaction product with an electrophile represented by the general formula (I), and deprotecting the obtained product without using a heavy metal: [in-line-formulae]RA3O(RA4O)k-1RA4O?M+??(V)[/in-line-formulae]wherein RA3 represents a linear; branched, or cyclic hydrocarbon group having 1 to 20 carbon atoms; RA4 represents an alkylene group having 2 to 8 carbon atoms; k represents an integer of 2 to 5; and M represents an alkali metal; wherein RA1a and RA1b each independently represent a protective group of the amino group, or one of RA1a and RA1b represents H and the other represents a protective group of the amino group, or RA1a and RA1b bind to each other to form a cyclic protective group, and the protective group is deprotectable without using a heavy metal; RA2 represents a linear, branched, or cyclic hydrocarbon group having 1 to 6 carbon atoms; and X represents a leaving group.