29898-07-5

Upstream product

• 29704-38-9 (4-nitrophenyl)acetic acid tert-butyl ester 
• 104-03-0 4-nitrobenzeneacetic acid 

Downstream Products

• 132974-31-3 Methoxy-(4-nitro-phenyl)-acetic acid tert-butyl ester 
• 129919-08-0 (1R,3R)-2,2,3-Trimethyl-1-(4-nitro-phenyl)-cyclopropanecarboxylic acid tert-butyl ester 
• 129919-08-0 (1R,3S)-2,2,3-Trimethyl-1-(4-nitro-phenyl)-cyclopropanecarboxylic acid tert-butyl ester 
• 29898-08-6 2-acetoxy-2-(4-nitrophenyl)acetic acid 
• 29704-35-6 tert-butyl 2-acetoxy-2-(4-nitrophenyl)acetate 
• 1236004-38-8 tert-butyl 5,6-dimethoxy-2-(4-nitrophenyl)-1,1a,2,7b-tetrahydrocyclopropa[c]chromene-1-carboxylate 

Relevant academic research and scientific papers

Erratum: Oxazaborolidinium Ion-Catalyzed Cyclopropanation of α-Substituted Acroleins: Enantioselective Synthesis of Cyclopropanes Bearing Two Chiral Quaternary Centers (J. Am. Chem. Soc. (2011) 133:51 (20708?20711) DOI: 10.1021/ja209270e)

Pages 20709 and 20710. In the published version of the paper, the trans:cis ratios of 2w and 2x were reversed. The revised results were confirmed by NOE experiments and comparison of the optical rotation data with reported values after transformation. The

From C1 to C3: Copper-Catalyzed gem-Bis(trifluoromethyl)olefination of α-Diazo Esters with TMSCF3

A Cu-catalyzed gem-bis(trifluoromethyl)olefination of α-diazo esters, using TMSCF3 as the only fluorocarbon source, has been developed and provides an exquisite method to access gem-bis(trifluoromethyl)alkenes. This unprecedented olefination pr

Oxazaborolidinium ion-catalyzed cyclopropanation of α-substituted acroleins: Enantioselective synthesis of cyclopropanes bearing two chiral quaternary centers

A catalytic synthetic route to highly functionalized chiral cyclopropane derivatives was developed by Michael-initiated cyclopropanation of α-substituted acroleins with aryl- and alkyl diazoacetates. In the presence of chiral (S)-oxazaborolidinium cation

Neighboring group participation in carbene chemistry. Effect of neighboring carboxylate group on carbene reactivities

Reactivities of (alkoxycarbonyl)carbenes are shown to be dramatically changed as one substitutes the ester group with carboxylate group. Thus, (methoxycarbonyl)- or carboxyl(4-nitrophenyl)carbene (2a and 2b, respectively), generated by photolysis of the corresponding diazo compounds in a binary mixture of 2-methyl-2-butene and methanol, gives both cycloaddition products to the butene and OH inserts products into methanol, the relative reactivities (kOH/kadd) being 0.3-0.5. In marked contrast, the "carboxylate" carbene (2c) generated from the sodium salt of the diazoacetate under the same conditions produces mostly the OH insertion product at the expense of the cyclopropanes, kOH/kadd being > 100. The marked effect of the carboxylate group is nicely explained in terms of the participation by the neighboring carboxylate group, which interacts strongly with the vacant p orbital of the singlet carbene, resulting in the reduction of the electrophilicity. The competition experiments using two sets of alkenes with different electron density also support the above idea Thus, 2c is > 2000 times more reactive to α-chloroacrylonitrile relative to l-hexene while 2a is only 3-4 times more reactive. More intriguingly, a Hammett treatment of the addition of 2 to a series of substituted styrenes demonstrates that philicity of the carbene is converted from electrophilic to nucleophilic in going from 2a to 2c. The geometries of the singlet state of the parent carboxylate carbene optimized by the ab initio molecular orbital using the STO-3G basis set is very much like that of α-lactone anion, where strong interaction between carboxylate oxygen anion and the vacant p orbital is possible. ESR studies show, however, that both 2a and 2c have a triplet ground state with comparable thermal stability and that the geometry of the triplet state is not affected by the neighboring carboxylate group.