Anticholinergic Agents. 4. Stereocontrolled Synthesis of Fluorinated Acetylcholine Antagonists; Syntheses of the Two 1-Cyclohexyl-1-(4-fluorophenyl)-3-piperidyl-1-propanols and their Methiodides.
摘要:
Four new putative muscarinic antagonists, (R)-(-)- and (S)-(+)-1-cyclohexyl-1-(4-fluorophenyl)-3-piperidyl-1-propanol and their methiodides, have been synthesised. Absolute configurations have been assigned on the basis of the anticipated chirality of the products of the Sharpless asymmetric epoxidation reaction.
Anticholinergic Agents. 4. Stereocontrolled Synthesis of Fluorinated Acetylcholine Antagonists; Syntheses of the Two 1-Cyclohexyl-1-(4-fluorophenyl)-3-piperidyl-1-propanols and their Methiodides.
摘要:
Four new putative muscarinic antagonists, (R)-(-)- and (S)-(+)-1-cyclohexyl-1-(4-fluorophenyl)-3-piperidyl-1-propanol and their methiodides, have been synthesised. Absolute configurations have been assigned on the basis of the anticipated chirality of the products of the Sharpless asymmetric epoxidation reaction.
A regiodefined synthesis of α-trimethylsilyl ketones catalyzed by rhodium(I) hydride complex
作者:Susumu Sato、Isamu Matsuda、Yusuke Izumi
DOI:10.1016/0022-328x(88)80214-6
日期:1988.4
Regiodefined synthesis of α-trimethylsilyl ketones is attained by one of three different routes: isomerization of β-trimethylsilyl allyl alcohols (route A), isomerization of β′-trimethylsilyl allyl alcohols (route B), and dehydrogenation of β-trimethylsilyl alcohols via transfer hydrogenation to α,β-enones (route C). All of these procedures are catalyzed efficiently by HRh(PPh3)4 at about 100 °C. Route
The rhodium catalyzed isomerization of α-, β-, and γ-silylated allylalcohols has been successfully applied to the selective synthesis of acylsilane, α-silyl ketones, and β-silyl ketones, respectively.
Nickel-catalyzed coupling reaction of sterically congested cis bromides and lithium alkenylborates
作者:Yuichi Kobayashi、Yuji Nakayama、Ryo Mizojiri
DOI:10.1016/s0040-4020(97)10206-x
日期:1998.2
Lithium alkenyl borates of general structure 5 (RT=alkenyl) couple with cis bromides 1 at room temperature overnight in the presence of NiCl2(PPh3)2 as a catalyst to furnish dienes of general structure 3 with retention of the olefin geometries present in both coupling partners. By using this reaction, cis, trans dienes 3 (R=TBDMS, TES, TBDPS; R1=n-C5H11, c-C6H11, R2=H; R3=n-C5H11, Ph) and cis,cis diene
通式5的烯基硼酸锂(R T =烯基)在室温下在作为催化剂的NiCl 2(PPh 3)2存在下与顺式溴化物1偶联过夜,以提供通式3的二烯并保留存在的烯烃几何结构在两个耦合伙伴中。通过使用该反应,顺式,二烯3(R = TBDMS,TES,TBDPS; R 1=n -C 5 H 11,c -C 6 H 11,R 2= H; R3 = n -C 5 H 11,Ph)和顺式,顺式二烯3(R = TBDMS; R 1 = R 2 = n -C 5 H 11; R 3 = H)以高收率合成。
Hexafluoroisopropanol as a Unique Solvent for Stereoselective Iododesilylation of Vinylsilanes
作者:Elizabeth A. Ilardi、Craig E. Stivala、Armen Zakarian
DOI:10.1021/ol800341z
日期:2008.5.1
Stereoselective preparation of iodoalkenes from vinylsilanes is described. 1,1,1,3,3,3-HexafluoroisopropanoI serves as a unique solvent that ensures high yields and stereoselectivities in the lododesilylation of a variety of functionalized substrates.
Stereoselective synthesis of (2,4)-dien-1-ols; key intermidiates for synthesis of sex pheromones of silk worm and of grape vine moth