Synthesis of Tetrahydro‐2(1H)quinazolinones, Cyclopenta[d]‐2(1H)pyrimidinones, and Their Thioxo Analogs from 2‐Trifluoroacetyl‐1‐methoxycycloalkenes
摘要:
A series of six (8)-alkyl-4-trifluoromethyl-5,6,7,8-tetrahydro-2(1H)quinazolinones, 4-trifluoromethyl-cyclopenta[d]-2(1H)pyrimidinones, and their thioxo analogs from the reaction of five beta-alkoxyvinyl trifluoromethyl ketones, derived from alkylated cyclohexanones and cyclopentanone with urea and thiourea, is reported. The reactions were carried out in a single step in propan-2-ol as solvent and boron trifluoride diethyl etherate as catalyst in 18-65% yield.
Synthesis of Tetrahydro‐2(1H)quinazolinones, Cyclopenta[d]‐2(1H)pyrimidinones, and Their Thioxo Analogs from 2‐Trifluoroacetyl‐1‐methoxycycloalkenes
摘要:
A series of six (8)-alkyl-4-trifluoromethyl-5,6,7,8-tetrahydro-2(1H)quinazolinones, 4-trifluoromethyl-cyclopenta[d]-2(1H)pyrimidinones, and their thioxo analogs from the reaction of five beta-alkoxyvinyl trifluoromethyl ketones, derived from alkylated cyclohexanones and cyclopentanone with urea and thiourea, is reported. The reactions were carried out in a single step in propan-2-ol as solvent and boron trifluoride diethyl etherate as catalyst in 18-65% yield.
Synthesis, 17O NMR spectroscopy and structure of 2-trifluoroacetyl-1-methoxycycloalkenes
作者:Helio G. Bonacorso、Michelle B. Costa、Sidnei Moura、Lucas Pizzuti、Marcos A.P. Martins、Nilo Zanatta、Alex F.C. Flores
DOI:10.1016/j.jfluchem.2005.08.003
日期:2005.10
Among the synthesis of a series of five well-known 2-trifluoroacetyl-1-methoxycycloalkenes derived from cyclopentanone and substituted cyclohexanones, this paper describes the synthesis of three new 2-trifluoroacetyl-1-methoxycycloalkenes derived from cycloheptanone, cyclooctanone and cyclododecanone in 60-68% yield. Subsequently, the O-17 NMR chemical shift analysis of the carbonyl and the methoxy groups for these cyclic molecules clearly showed the electron push-pull phenomenon and revealed large and irregular variations of O-17 NMR chemical shifts with the ring size. Finally, a more stable conformation of these trifluoroacetyl-containing cycloalkenes was determined by energy minimization calculations using Austin Model 1 (AM1) semi-empirical method and correlations between O-17 NMR data and torsion angles or oxygen net charge calculated by AMI semi-empirical method were performed. (c) 2005 Elsevier B.V. All rights reserved.
Synthesis of Tetrahydro‐2(1<i>H</i>)quinazolinones, Cyclopenta[<i>d</i>]‐2(1<i>H</i>)pyrimidinones, and Their Thioxo Analogs from 2‐Trifluoroacetyl‐1‐methoxycycloalkenes
作者:Helio G. Bonacorso、Michelle B. Costa、Itamar S. Lopes、Marlí R. Oliveira、Roberta L. Drekener、Marcos A. P. Martins、Nilo Zanatta、Alex F. C. Flores
DOI:10.1080/00397910500278818
日期:2005.12
A series of six (8)-alkyl-4-trifluoromethyl-5,6,7,8-tetrahydro-2(1H)quinazolinones, 4-trifluoromethyl-cyclopenta[d]-2(1H)pyrimidinones, and their thioxo analogs from the reaction of five beta-alkoxyvinyl trifluoromethyl ketones, derived from alkylated cyclohexanones and cyclopentanone with urea and thiourea, is reported. The reactions were carried out in a single step in propan-2-ol as solvent and boron trifluoride diethyl etherate as catalyst in 18-65% yield.