17082-05-2Relevant articles and documents
The Electronic Interaction between the Methyl Group and Trigonal Carbon
Lambert, Joseph B.,Nienhuis, Ronald J.
, p. 6659 - 6665 (1980)
The nature of the interaction between methyl and a trigonal carbon has been examined by the effect of substituents on the methyl rotational barrier.Barriers have been measured for para-substituted toluenes and for cis- and trans-substituted propenes by the motional effects of methyl rotation on dipole-dipole spin-lattice relaxation.The toluene barriers exhibit a fair correlation with ?I and a very poor one with ?R.Thus hyperconjugation cannot be a major factor in determining the methyl rotational barrier.The propene barriers, particularly in the cis series, also correlate with ?I but have a better correlation with ?R than do the toluenes.Examination of all the 13C chemical shifts showed that the rotational barriers correlate only with the ortho carbon in the toluenes and with the 2-carbon (methyl substituted) in the propenes.These results suggest that the methyl rotational barrier is primarily sensitive to the nature of the ortho C-H bond in the toluenes and the α-C-H bond in the propenes.The ?R and ?I correlations are in accord with this model, since the ortho toluene carbon cannot interact directly through resonance with the para substituent but must depend on polar interactions.In the propenes, on the other hand, electron density at the α-carbon is determined by both inductive and resonance effects.The major factor in determining these barriers is the electron density at the critical carbon center, which is the ortho carbon for the toluenes and the α-carbon for the propenes.
CuI-Catalysed Enantioselective Alkyl 1,4-Additions to (E)-Nitroalkenes and Cyclic Enones with Phosphino-Oxazoline Ligands
Shin, Minkyeong,Gu, Minji,Lim, Sung Soo,Kim, Min-Jae,Lee, JuHyung,Jin, HyeongGyu,Jang, Yun Hee,Jung, Byunghyuck
supporting information, p. 3122 - 3130 (2018/07/06)
Catalytic enantioselective conjugate additions of simple alkyl groups to nitroalkenes or cyclic enones that result in the formation of tertiary C–C bonds are described. For these stereoselective addition reactions, new chiral phosphino-oxazoline ligands w
Metal nitrate driven nitro Hunsdiecker reaction with α,β-unsaturated carboxylic acids under solvent-free conditions
Ramgopal,Ramesh,Chakradhar,Reddy, N. Maasi,Rajanna
, p. 4043 - 4045 (2008/02/04)
Hunsdiecker reactions with α,β-unsaturated carboxylic acids were conducted under solvent-free conditions in the presence of a few drops of HNO3 together with a variety of metal nitrates [Mg(NO3)2, Sr(NO3)2], Al(NO3)3, Ca(NO3)2, Ni(NO3)2, Cd(NO3)2, Zn(NO3)2, Hg(NO3)2, AgNO3, ZrO(NO3)2, UO2(NO3)2, Th(NO3)2] or ammonium nitrate. α,β-Unsaturated aromatic carboxylic acids underwent nitro decarboxylation to afford β-nitro styrenes in moderate to good yields, while α,β-unsaturated aliphatic carboxylic acids underwent decarboxylation to yield the corresponding nitro derivatives.