6937-03-7Relevant articles and documents
Spin-Center Shift-Enabled Direct Enantioselective α-Benzylation of Aldehydes with Alcohols
Nacsa, Eric D.,MacMillan, David W. C.
supporting information, p. 3322 - 3330 (2018/03/13)
Nature routinely engages alcohols as leaving groups, as DNA biosynthesis relies on the removal of water from ribonucleoside diphosphates by a radical-mediated "spin-center shift" (SCS) mechanism. Alcohols, however, remain underused as alkylating agents in synthetic chemistry due to their low reactivity in two-electron pathways. We report herein an enantioselective α-benzylation of aldehydes using alcohols as alkylating agents based on the mechanistic principle of spin-center shift. This strategy harnesses the dual activation modes of photoredox and organocatalysis, engaging the alcohol by SCS and capturing the resulting benzylic radical with a catalytically generated enamine. Mechanistic studies provide evidence for SCS as a key elementary step, identify the origins of competing reactions, and enable improvements in chemoselectivity by rational photocatalyst design.
2-aminopyridine-4-methyl formate synthesizing method
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Paragraph 0021-0031; 0032-0038; 0042-0045; 0049-0051, (2018/04/21)
The invention discloses a 2-aminopyridine-4-methyl formate synthesizing method which comprises the following steps: firstly, preparing a Fe-Mn-Mo-TiO catalyst; then mixing 2-amino-4-methyl pyridine with water; heating to 40 to 50 DEG C; adding a Fe-Mn-Mo-TiO catalyst; stirring; dropwise adding dilute nitric acid; stirring and reacting for 3 to 4h; cooling to room temperature; filtering; adjustinga pH of filtrate as 9 to 10; then adding methyl alcohol; heating, refluxing and reacting for 1 to 2h; performing reduced pressure distillation to remove the methyl alcohol; utilizing dichloromethane to perform repeated extraction; combining organic phases; performing reduced pressure distillation to remove the dichloromethane; obtaining the 2-aminopyridine-4-methyl formate. The synthesizing methoddisclosed by the invention has the advantages of simpleness in operation, moderate condition, smaller byproducts, high product purity and higher product yield.
New method for preparation of (2-aminopyridin-4-yl)methanol
Lifshits,Ostapchuk,Brel
, p. 744 - 745 (2015/07/02)
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