13294-67-2Relevant academic research and scientific papers
CIDNP STUDY OF REACTIONS OF KETYLS AND DIANIONS DERIVED FROM BENZOPHENONE AND FLUORENONE WITH ACETIC ANHYDRIDE
Honzl, Jan,Lovy, Jan
, p. 1885 - 1892 (1984)
A study is presented of 1H and 13C CIDNP effects in the reactions of Na and Li salts of ketyls and dianions derived from benzophenone and fluorenone with acetic anhydride in tetrahydrofuran and dimethoxyethane.CIDNP effects were obse
REACTION OF DILITHIUM BENZOPHENONE, DILITHIUM 9-FLUORENONE AND THE LITHIUM SALT OF BENZOPHENONE KETYL WITH CHLORIDES AND ANHYDRIDES OF CARBOXYLIC ACIDS
Honzl, J.,Metalova, M.
, p. 297 - 306 (1980)
The reaction of dilithium benzophenone and the lithium salt of benzophenone ketyl with anhydrides and chlorides of benzoic and acetic acid and the reaction of dilithium 9-fluorenone with acetic anhydride were investigated.In addition to the expected products Ar2C(COR)OCOR, products of the type Ar2C=CR(OCOR) were also obtained, and in the case of reactions with acetyl chloride and acetic anhydride, products of the type Ar2CH(OCOR).ESR studies showed that ketyl is formed in the reaction of dilithium benzophenone with acetic anhydride, and the ClDNP method revealed thatbenzhydryl acetate is formed, at least in part, by hydrogen transfer to a free radical produced by O-acetylation of the ketyl.The results suggest a competition between addition and electron transfer reactions.
Conversion of propargylic alcohols to β-oxo esters catalyzed by novel ruthenium-phosphoramidite complexes
Costin, Stephen,Rath, Nigam P.,Bauer, Eike B.
supporting information; experimental part, p. 2414 - 2424 (2009/11/30)
A series of half-sandwich phosphoramidite complexes of ruthenium were synthesized and employed as catalysts in the atom-economical formation of β-oxo esters from carboxylic acids and propargylic alcohols. Reaction of the phosphoramidites (R)-BINOL-PNR2 (R=Me, 1a; i-Pr, 1b; benzyl, 1c) and (rac)-6,6′-dibromo-BINOL-PNMe2 (1d) with the dimeric p-cymene-ruthenium dichloride complex, [RuCl2(p-cymene)]2, gave the complexes [RuCl2(p-cymene)(L)] (L=1a, 7a; 1b, 7b; 1c, 7c; 1d, 7d) in 96-66% yield. Accordingly, reaction of (R)-BINOL(8H)-PNMe2 (2a) and (R)-BINOL(8H)-PN-(benzyl)2 (2b) with [RuCl2(p-cymene)] 2 afforded the complexes [RuCl2(p-cymene)(L)] (L=2a, 8a; 2b, 8b) in 82% and 86% yield. In a similar reaction, treatment of (R)-BIPHEN-PNMe2 (9) with [RuCl2(p-cymene)] 2 gave the complex [RuCl2(p-cymene)(9)] (11) in 60% yield. Finally, phosphoramidite 1b reacted with [RuCl2(C6Me 6)]2 to give [RuCl2(C6Me 6)(1b)] (12) in 78% yield. All novel complexes are catalytically active in the formation of β-oxo esters from propargylic alcohols and carboxylic acids. Standard conditions involve cyclohexane solvent, propargylic alcohol (1.0 equiv.), carboxylic acid (1.0 equiv.), ruthenium catalyst (1.5 mol%), and 90°C for 5-18 h. Isolated yields of the β-oxo esters range from 87 to 16% and show broad substrate generality. The reaction proceeds without racemization if a chiral propargylic alcohol is employed. The method is practical as no additives are required and the exclusion of oxygen and moisture is not needed. Complex 7c turned out to be the most effective catalyst (5 h reaction time), showing that the ligand structure has a profound impact on the catalytic performance. The crystal structure of 7a was determined, confirming an octahedral coordination geometry about the ruthenium center.
Analogues of oxybutynin. Synthesis and antimuscarinic and bladder activity of some substituted 7-amino-1-hydroxy-5-heptyn-2-ones and related compounds
Carter,Noronha-Blob,Audia,Dupont,McPherson,Natalie Jr.,Rzeszotarski,Spagnuolo,Waid,Kaiser
, p. 3065 - 3074 (2007/10/02)
Oxybutynin chloride [4-(diethylamino)-2-butynyl α-cyclohexyl-α-hydroxybenzeneacetate hydrochloride, Ditropan] is widely used for the relief of symptoms in neurogenic bladder. This is a result of its combined anticholinergic, antispasmodic, and local anesthetic activities. In a study directed toward development of agents possessing the beneficial properties of oxybutynin, but having a longer duration of action, a series of metabolically more stable keto analogues of the parent ester, i.e. substituted 7-amino-1-hydroxy-5-heptyn-2-ones along with some analogues and derivatives, was prepared and evaluated for in vitro and in vivo antimuscarinic action in guinea pig preparations. Several members of the series were potent antimuscarinics having a longer duration of activity than that of oxybutynin in a guinea pig cystometrogram model. On the basis of its in vitro and in vivo antimuscarinic activity, coupled with a 5-fold greater duration of action than that of oxybutynin, 1-cyclobutyl-7-(dimethylamino)-1-hydroxy-1-phenyl-5-heptyn-2-one (14b) was selected for clinical evaluation.
