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Upstream product

• 1696-17-9 N,N-diethylbenzamide 
• 614-17-5 N-ethylbenzamide 
• 98-88-4 benzoyl chloride 

Relevant academic research and scientific papers

Organoiridium catalyzed hydrogen isotope exchange: Ligand effects on catalyst activity and regioselectivity

Several iridium complexes [Ircod)L2]X (L = phosphine ligand) were used as precatalysts for the exchange labeling of a range of model compounds with deuterium gas. Complexes with monodentate L (e.g. PMePh2, PPh3 and substituted derivatives thereof) catalyzed exchange selectively of hydrogens four bonds away from a coordinative heteroatom in the substrate, while those with bidentate L (bis(diphenylphosphino)ethane (dppe) and bis(diphenylphosphino)butane) catalyzed exchange of hydrogens both four and five bonds away from a coordinative heteroatom. At heavier loadings, some monodentate complexes also catalyzed five-bond labeling of some substrates. [Ir(cod)(dppe)]BF4 catalyzed the tritium labeling of methyl 6-methoxynaphth-2-ylacetate at C1 and C3.

DILITHIATED SYNTHONS OF TERTIARY BENZAMIDES, PHTHALAMIDES, AND O,O'-ARYL DICARBAMATES

Dilithiated species 1, 2, and 3, generated by metal-halogen exchange and directed ortho metalation, undergo reaction with electrophiles to afford, in high yield, polysubstituted aromatics 6, 7, and 8 respectively; 9 is formed via a bis anionic Fries rearr

A COMPARISON OF SECONDARY AND TERTIARY AMIDES AS DIRECTORS OF ORTHO AND ADJACENT BENZYLIC LITHIATION AND OF ASYMMETRIC INDUCTION IN ORTHO LITHIATED BENZAMIDES

Comparisons are made between the influence of secondary and tertiary amides on ortho and adjacent benzylic metallations of benzamides.In the intramolecular competition offered by N,N-diethyl-N-ethylterephthalamide (1) the tertiary amide is the more effective director of ortho lithiation, while the secondary amide is better in the intermolecular competitions offered by the pairs N-ethyl-(9):N,N-diethylbenzamide(10) and N-isopropyl-(11):N,N-diisopropylbenzamide(12).Both secondary and tertiary amides are found to direct metallation ortho to the amide in the 2-isopropylbenzamides 25 and 26; however, benzylic metallation is observed with secondary 2-ethyl- and 2-methylbenzamides 21 and 22 and with the tertiary 2-ethylbenzamide 19.Magnetic non-equivalence is noted for the anti-N-methylene group of 19.The reaction of an ortho lithio (S)-O-methyl-N-benzoylleucinol (34) with 1-naphthaldehyde-1-d gives, after lactonization, 3-(1-naphthyl-1-d)-phthalide with 10percent enantiomeric excess.The phthalide can be obtained in high enantiomeric purity by separation of the diastereoisomers prior to cyclization.Control experiments establish that the observed asymmetric induction is attributable to diastereomeric transition states.The corresponding tertiary benzamide is ineffective in inducing asymmetry.Structural and mechanistic rationales are offered for these observations.

The Tertiary Amide as an Effective Director of Ortho Lithiation

The tertiary amides N,N-diethylbenzamide (1) and N,N-diisopropylbenzamide (3) give the ortho-lithiated species 2 on treatment with sec-BuLi/TMEDA or n-BuLi/TMEDA, respectively, at -78 deg.Lithiation of 1 followed by rection with either methyl iodide, ethyl iodide, benzophenone, acetone, benzaldehyde, or trimethoxyborane-hydrogen peroxide gives the expected ortho substituted product.Intramolecular competition between the diethyloamido and chloro, methoxyl, sulfonamido, (dimethylamino)methyl, or oxazolino functions in ortho- and para-substituted benzamides establishes the tertiary amido group to be more effective in directing metalation than any noncarboxamide functional group under the prescribed conditions.Complimentarity of directing effects is observed with the chloro and methoxyl groups in the meta-substituted diethylbenzamides but not with the methyl group.The secondary amide is found to have a directing ability comparable to the tertiary amide with sec-BuLi/TMEDA at -78 deg in THF although the yields are low. 13C NMR chemical shifts are particularly useful for the structural assignments which are confirmed chemically by lactonization of some products.A labeling study with N,N-diisopropyl-2,6-dideuteriobenzamide suggests that lithiation of the ortho position of 3 is direct and not the result of rearrangement of an initially formed α-aza anion.Control of metalation at the ortho or benzylic position by proper selection of the organolithium base is illustrated for N,N-diisopropyl-p-toluamide.The value of the tertiary amide for control of ortho lithiations and regiospecific aromatic substitutions is noted.