厦门大学化学化工学院：《有机化学》课程教学资源（课件讲稿，双语版）第二十一章 酚和芳香卤代烃：芳香亲核取代反应（21.10）Quinones 醌

ORGANIC CHEMISTRY Chapter 21 21.10 Quinones 醌 Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 21 21.10 Quinones 醌

ORGANIC CHEMISTRY Chapter 21 o Oxidation of hydroquinone produces p-benzoquinone o Oxidant: Na2 Cr2O,(KSO3)2NO--Fremy's salt (potassium nitrosodisulfonate) OH 2e +2H+ +2e O Hydroquinone p-Benzoquinone o This reaction is reversible; p-benzoquinone is easily reduced by mild reducing agents to hydroquinone SnCh, H2O p-Benzoquinone Hydroquinone (KSO3)NO Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 21 Oxidation of hydroquinone produces p-benzoquinone. Oxidant: Na2Cr2O7, (KSO3)2NO— Fremy’s salt (potassium nitrosodisulfonate) OH OH 2e- +2e￾O O + 2H+ Hydroquinone p-Benzoquinone This reaction is reversible; p-benzoquinone is easily reduced by mild reducing agents to hydroquinone. p-Benzoquinone Hydroquinone SnCl2, H2O (KSO3)2NO

ORGANIC CHEMISTRY Chapter 21 o Quinones are an interesting and valuable class of compounds because of their oxidation-reduction,or redox, properties o The redox properties of quinones are important to the functioning of living cells, where compounds called ubiquinones(iz e)act as biochemical oxidizing agents to mediate the electro-transfer processes involved in energy production OH CHO CH +2e^.+2 H CH2O CH 2e.2H CHO H CH2O H CH OH CH3 Ubig Quinones(n=6 10 Ubiquinol(hydroquinone form) (coenzymes Q) Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 21 Quinones are an interesting and valuable class of compounds because of their oxidation-reduction, or redox, properties. The redox properties of quinones are important to the functioning of living cells, where compounds called ubiquinones(泛醌) act as biochemical oxidizing agents to mediate the electro-transfer processes involved in energy production. O O CH3O CH3O CH3 H CH3 n OH OH CH3O CH3O CH3 H CH3 n +2e- , +2H+ 2e- , 2H+ Ubiquinones (n=6 10) Ubiquinols (hydroquinone form) (coenzymes Q)

ORGANIC CHEMISTRY Chapter 21 CH CH CHCH=C(CHCHCH2 CH)3CH CH Vitamine K1 The substance first indentified as essential for the normal clotting of blood OH OH 1, 4-Naphthoquinone Alizarin 茜素 A red pigment extracted from the roots of the madder plant Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 21 O O 1,4-Naphthoquinone O O CH3 CH2CH C(CH2CH2CH2CH)3CH3 CH3 CH3 Vitamine K1 The substance first indentified as essential for the normal clotting of blood O O OH OH Alizarin 茜素 A red pigment extracted from the roots of the madder plant