Dichlorination of α-Diazo-β-dicarbonyls Using (Dichloroiodo)benzene
作者:Graham Murphy、Keith Coffey
DOI:10.1055/s-0034-1380304
日期:2015.5
α-Diazo-β-dicarbonyl compounds were chlorinated using (dichloro)iodobenzene and an activating catalyst. A broad range of reaction rates was observed, which paralleled the relative stability/nucleophilicity of the diazo compounds. Acyclic diazocarbonyls reacted faster than cyclics, and β-diketones were much faster to react than β-keto esters or β-diesters. Lewis acid activation was used for the first
Pd-Catalyzed Allylic Alkylation Cascade with Dihydropyrans: Regioselective Synthesis of Furo[3,2-<i>c</i>]pyrans
作者:Mark J. Bartlett、Claire A. Turner、Joanne E. Harvey
DOI:10.1021/ol400902d
日期:2013.5.17
A regioselective palladium-catalyzed allylic alkylation cascade forms furo[3,2-c]pyrans from various cyclic β-dicarbonyl bis-nucleophiles and 3,6-dihydro-2H-pyran bis-electrophiles. The combination of allylic carbonate and anomeric siloxy leaving groups in the dihydropyran substrate allows control of the many regiochemical possibilities in this reaction. Annulation proceeds stereoconvergently to give
区域选择性钯催化的烯丙基烷基化级联反应由各种环状β-二羰基双亲核试剂和3,6-二氢-2 H-吡喃双亲电试剂形成呋喃[3,2- c ]吡喃。二氢吡喃底物中的烯丙基碳酸酯和异头甲硅烷氧基离去基团的组合允许控制该反应中许多区域化学的可能性。环合进行立体会聚,以从顺式或反式取代的起始原料产生顺式融合的呋喃吡喃。
Method of combatting coronary and vascular diseases
申请人:Bayer Aktiengesellschaft
公开号:US04532248A1
公开(公告)日:1985-07-30
1,4-Dihydropyridines of the formula ##STR1## in which n is 0,1 or 2, and R.sup.1 to R.sup.7 can have a wide variety of meanings, which possess inotropic action, and many of which are new, are useful in increasing the influx of Ca.sup.++ into cells, particularly in combatting coronary and vascular diseases, hypertension swelling in the mucous membranes and diseases involving increased blood sugar or an incorrect salt and fluid balance.
Regioselective Addition of 1,3-Dicarbonyl Dianions to Carbonyl Compounds: One Pot Lactonization and Ketalization of δ-Hydroxy-β-keto Esters to Protected Pyrone Derivatives
作者:Manas K. Ghorai、Sandipan Halder、Sauvik Samanta
DOI:10.1071/ch12062
日期:——
strategy for the synthesis of 6-substituted-2-pyrone derivatives, by BF3·OEt2 mediated one pot cyclization and keto-protection of δ-hydroxy-β-keto esters, obtained via regioselective addition of 1,3-dicarbonyl dianion of ethyl acetoacetate to aldehydes and ketones is described.