86568-88-9Relevant academic research and scientific papers
Metal-catalyzed oxidative cyclizations of a,c-biladiene salts bearing 1- and/or 19-arylmethyl substituents: Macrocyclic products and their chemistry
Lin, Jack J.,Gerzevske, Kevin R.,Liddell, Paul A.,Senge, Mathias O.,Olmstead, Marilyn M.,Khoury, Richard G.,Weeth, Brent E.,Tsao, Stephanie A.,Smith, Kevin M.
, p. 4266 - 4276 (2007/10/03)
Several 1-mono- and 1,19-bis(p-arylmethyl)-a,c-biladiene salts were prepared and subjected to either copper(II)- or chromium(III)-assisted oxidative cyclization to yield numerous products in which the 1- or 19- substituent is adapted, eliminated, or rearranged to other points on the tetrapyrrole. For example, cyclization using copper(II) acetate of 19- ((ethoxycarbonyl)methyl)-2,3,7,8,12,13,17,-18-octamethyl-19-(p-tolylmethyl)- a,c-biladiene dihydrobromide (25) yielded the copper(II) 20- ((ethoxycarbonyl)methyl)-1-(p-tolylmethyl)-2,3,7,8,12,13,17,18-octamethyl- 1,20-dihydroporphyrin (42), copper(II) 20-(ethoxycarbonyl)-3-methylidene- 2,3,7,8,12,13,17,18-octamethyl-2-(p-tolylmethyl)-chlorin (44), copper(II) 20- (ethoxycarbonyl)-2-methylidene-2,3,7,8,12,13,17,18-octamethyl-3-(p- tolylmethyl)chlorin (45), and three porphyrins: copper(II) 20- (ethoxycarbonyl)-2,3,7,8,12,13,17,18-octamethylporphyrin (3), copper(II) 2,3,7,8,12,13,17,18-octamethyl-20-p-tolylporphyrin (50), and copper(II) 20- (ethoxycarbonyl)-2,3,7,8,12,13,17,18-octamethyl-5-(p-tolylmethyl)porphyrin (47). Formation of porphyrin 47 and the intermediate chlorins 44 and 45 suggests the stepwise migration of the arylmethyl group from the 1-position in compound. 42. The isolation of products from cyclization reactions of various 1,19-arylmethyl-substituted a,c-biladiene salts provides further insight into the mechanisms of metal-assisted oxidative cyclization of a,c- biladiene salts to give cyclic tetrapyrroles. Macrocyclizations of a,c- biladienes such as 25 using chromium(III) afford good yields of the metal- free 1-substituted compounds such as 43.
Novel Macrocycles from Metal-Catalyzed Oxidative Cyclizations of a,c-Biladiene Salts
Liddell, Paul A.,Gerzevske, Kein R.,Lin, Jack J.,Olmstead, Marilyn M.,Smith, Kevin M.
, p. 6681 - 6691 (2007/10/02)
From the metal-promoted oxidative cyclization of several 1,19-disubstituted a,c-biladiene dihydrobromide salts, a number of novel macrocycles were prepared.For example, the cyclization of 1,19-bis(2-(methoxycarbonyl)ethyl)-2,3,7,8,12,13,17,18-octamethyl-a,c-biladiene dihydrobromide salt (10) with copper(II) acetate afforded copper(II) 20-((methoxycarbonyl)methyl)-1-(2-(methoxycarbonyl)ethyl)-2,3,7,8,12,13,17,18-octamethyl-1,2a0-dihydroporphyrin (13) (39percent yield), which, upon demetalation, yielded the metal-free 20-((methoxycarbonyl)methyl)-1-(2-(methoxycarbonyl)ethyl)-2,3,7,8,12,13,17,18-octamethyl-1,20-dihydroporphyrin (14) (48percent yield).With the substrate 19-((ethoxycarbonyl)methyl)-1-(2-(methoxycarbonyl)ethyl)-2,3,7,8,12,13,17,18-octamethyl-a,c-biladiene dihydrobromide (15), the metal-catalyzed cyclization process produced copper(II) 20-(ethoxycarbonyl)-1-(2-(methoxycarbonyl)ethyl)-2,3,7,8,12,13,17,18-octamethyl-1,20-dihydroporphyrin (18) (27percent yield) and copper(II) 20-(ethoxycarbonyl)-2-(2-(methoxycarbonyl)ethyl)-2,7,8,12,13,17,18-heptamethyl-3-methylidene-2,3-dihydroporphyrin (23) (19percent yield).Upon demetalation of the copper dihydroporphyrin 18, 20'-(ethoxycarbonyl)-20-(2-(methoxycarbonyl)ethyl)-2,3,7,8,12,13,17,18-octamethyl-20'-homoporphyrin (28) (16.5percent yield) was isolated; demetalation of copper(II) 20-(ethoxycarbonyl)-2-(2-(methoxycarbonyl)ethyl)-2,7,8,12,13,17,18-heptamethyl-3-methylidene-2,3-dihydroporphyrin (23) yielded the free base 20-(ethoxycarbonyl)-2-(2-(methoxycarbonyl)ethyl)-2,7,8,12,13,17,18-heptamethyl-3-methylidene-2,3-dihydroporphyrin (25) (24percent yield).Using chromium(III) hydroxy acetate as the oxidant (in place of copper(II)), 1,2,3,7,8,12,13,17,18-nonamethyl-1,20-dihydroprphyrin (5) (55-62percent) was obtained from the 1,2,3,7,8,12,13,17,18,19-decamethyl-a,c-biladiene salt 3.Mechanisms of macrocycle formation from a,c-biladiene salts, promoted by either copper(II) or chromium(III), appear to proceed via pathways closely resembling the electrochemical cyclization reaction of 1,19-dimethyl-a,c-biladiene salts.
Sapphyrins: Novel Aromatic Pentapyrrolic Macrocycles
Bauer, Victor J.,Clive, Derrick L.J.,Dolphin, David,Paine, John B.,Harris, Francis L.,et al.
, p. 6429 - 6436 (2007/10/02)
Sapphyrins are pentapyrrolic macrocycles containing one direct link and four bridging methine groups between the five pyrrolic subunits.The syntheses of decamethylsapphyrin, other peripherally alkylated derivatives, and metal complexes are described.The p
