Variable electronic properties of the CSNMe2 thioamide group
摘要:
The sigma-I value for the CSNMe2 group has been determined and the value of 0.23 indicates that this group is inductively electron withdrawing. The effect of the p-CSNMe2 group on the solvolysis rate of cumyl chloride has also been determined and, relative to the p-H analogue, this group has a negligible effect on rate. p-CSNMe2 substitution slows the hydrolysis rate of substituted benzaldehyde dimethyl acetals. p-CSNMe2 substitution enhances the solvolysis rate of ArCH(OMs)PO(OEt)2. These variable rate effects on reactions involving cationic intermediates have been interpreted in terms of variable electronic properties of the CSNMe2 group. This group can be cation stabilizing, electroneutral, or cation destabilizing, depending on the charge demands of specific cations. This is a result of a conjugative interaction of CSNMe2 with a cationic center and resultant delocalization of positive charge onto sulfur. The importance of such conjugation is a function of the amount of transition-state charge developed on the carbon bearing the CSNMe2 group. The electronic effects of the amphielectronic p-CSNMe2 group are compared to the more conventional effects of CONMe2 and the m-CSNMe2 analogues.
Variable electronic properties of the CSNMe2 thioamide group
摘要:
The sigma-I value for the CSNMe2 group has been determined and the value of 0.23 indicates that this group is inductively electron withdrawing. The effect of the p-CSNMe2 group on the solvolysis rate of cumyl chloride has also been determined and, relative to the p-H analogue, this group has a negligible effect on rate. p-CSNMe2 substitution slows the hydrolysis rate of substituted benzaldehyde dimethyl acetals. p-CSNMe2 substitution enhances the solvolysis rate of ArCH(OMs)PO(OEt)2. These variable rate effects on reactions involving cationic intermediates have been interpreted in terms of variable electronic properties of the CSNMe2 group. This group can be cation stabilizing, electroneutral, or cation destabilizing, depending on the charge demands of specific cations. This is a result of a conjugative interaction of CSNMe2 with a cationic center and resultant delocalization of positive charge onto sulfur. The importance of such conjugation is a function of the amount of transition-state charge developed on the carbon bearing the CSNMe2 group. The electronic effects of the amphielectronic p-CSNMe2 group are compared to the more conventional effects of CONMe2 and the m-CSNMe2 analogues.
[EN] PROCESS FOR PREPARING N-(5-CHLORO-2-ISOPROPYLBENZYL)CYCLOPROPANAMINE<br/>[FR] PROCÉDÉ POUR LA PRÉPARATION DE N-(5-CHLORO-2-ISOPROPYLBENZYL)CYCLOPROPANAMINE
申请人:BAYER CROPSCIENCE AG
公开号:WO2013160387A1
公开(公告)日:2013-10-31
The present invention relates to a process for preparing N-(5-chloro-2-isopropylbenzyl)cyclopropanamine by hydrogenation of N-[(5-chloro-2-isopropylphenyl)methylene]cyclopropanamine over specific platinum catalysts.
Rates of Solvolysis of the Halophenyldimethylcarbinyl Chlorides. The Effect of Halogen Substituents upon the Rates of Electrophilic Reactions<sup>1-3</sup>
作者:Herbert C. Brown、Y. Okamoto、George Ham
DOI:10.1021/ja01565a037
日期:1957.4
PROCESS FOR PREPARING N-(5-CHLORO-2-ISOPROPYLBENZYL)CYCLOPROPANAMINE
申请人:Bayer CropScience AG
公开号:EP2841413A1
公开(公告)日:2015-03-04
Access to “Friedel–Crafts-Restricted” <i>tert</i>-Alkyl Aromatics by Activation/Methylation of Tertiary Benzylic Alcohols
作者:Joshua A. Hartsel、Derek T. Craft、Qiao-Hong Chen、Ming Ma、Paul R. Carlier
DOI:10.1021/jo202371c
日期:2012.4.6
Herein we describe a two-step protocol to prepare m-tert-alkylbenzenes. The appropriate tertiary benzylic alcohols are activated with SOCl2 or concentrated HCl and then treated with trimethylaluminum, affording the desired products in 68-97% yields (22 examples). This reaction sequence is successful in the presence of a variety of functional groups, including acid-sensitive and Lewis-basic groups. In addition to t-Bu groups, 1,1-dimethylpropyl and 1-ethyl-1-methylpropyl groups can also be installed using this method.
Variable electronic properties of the CSNMe2 thioamide group
作者:Xavier Creary、Timothy Aldridge
DOI:10.1021/jo00013a038
日期:1991.6
The sigma-I value for the CSNMe2 group has been determined and the value of 0.23 indicates that this group is inductively electron withdrawing. The effect of the p-CSNMe2 group on the solvolysis rate of cumyl chloride has also been determined and, relative to the p-H analogue, this group has a negligible effect on rate. p-CSNMe2 substitution slows the hydrolysis rate of substituted benzaldehyde dimethyl acetals. p-CSNMe2 substitution enhances the solvolysis rate of ArCH(OMs)PO(OEt)2. These variable rate effects on reactions involving cationic intermediates have been interpreted in terms of variable electronic properties of the CSNMe2 group. This group can be cation stabilizing, electroneutral, or cation destabilizing, depending on the charge demands of specific cations. This is a result of a conjugative interaction of CSNMe2 with a cationic center and resultant delocalization of positive charge onto sulfur. The importance of such conjugation is a function of the amount of transition-state charge developed on the carbon bearing the CSNMe2 group. The electronic effects of the amphielectronic p-CSNMe2 group are compared to the more conventional effects of CONMe2 and the m-CSNMe2 analogues.