@article {43726,
	title = {Secondary interactions arrest the hemiaminal intermediate to invert the modus operandi of schiff base reaction: a route to benzoxazinones},
	journal = {Journal of Organic Chemistry},
	volume = {82},
	year = {2017},
	month = {APR},
	pages = {4342-4351},
	type = {Article},
	abstract = {Discovered by Hugo Schiff, condensation between amine and aldehyde represents one of the most ubiquitous reactions in chemistry. This classical reaction is widely used to manufacture pharmaceuticals and fine chemicals. However, the rapid and reversible formation of Schiff base prohibits formation of alternative products, of which benzoxazinones are an important class. Therefore, manipulating the reactivity of two partners to invert the course of this reaction is an elusive target. Presented here is a synthetic strategy that regulates the sequence of Schiff base reaction via weak secondary interactions. Guided by the computational models, reaction between 2,3,4,5,6-pentafluoro-benzaldehyde with 2-amino-6methylbenzoic acid revealed quantitative (99\%) formation of 5-methyl-2-(perfluoropheny01,2-dihydro-4H-benzo[d][1,3]oxazin-4-one (15). Electron donating and electron withdrawing ortho-substituents on 2-aminobenzoic acid resulted in the production of benzoxazinones 936. The mode of action was tracked using low temperature NMR, IN vis spectroscopy, and isotopic (O-18) labeling experiments. These spectroscopic mechanistic investigations revealed that the hemiaminal intermediate is arrested by the hydrogen-bonding motif to yield benzoxazinone. Thus, the mechanistic investigations and DFT calculations categorically rule out the possibility of in situ imine formation followed by ring-closing, but support instead hydrogen-bond assisted ring-closing to prodrugs. This unprecedented reaction represents an interesting and competitive alternative to metal catalyzed and classical methods of preparing benzoxazinone.},
	doi = {10.1021/acs.joc.7b00352},
	author = {Patel, Ketan and Deshmukh, Satej S. and Bodkhe, Dnyaneshwar and Mane, Manoj and Vanka, Kumar and Shinde, Dinesh and Rajamohanan, Pattuparambil R. and Nandi, Shyamapada and Vaidhyanathan, Ramanathan and Chikkali, Samir H.}
}
@article {43815,
	title = {Synthesis of meta-substituted monodentate phosphinite ligands and implication in hydroformylation},
	journal = {Journal of Chemical Sciences},
	volume = {129},
	year = {2017},
	month = {AUG},
	pages = {1143-1152},
	type = {Article},
	abstract = {Synthesis of meta-substituted phosphinite ligands 3,3{\textquoteright}-(methoxyphosphanediyl) bis(N, N-diethylaniline) (4a) and methoxybis(3-methoxyphenyl) phosphane (4b), in high yields, has been demonstrated. Typical phosphorus chemical shift between 110-120 ppm, appearance of methoxy protons and corresponding carbon, as well as ESI-MS spectra unambiguously confirmed the existence of phosphinite ligands 4a and 4b. To demonstrate the synthetic usefulness of 4a and 4b, these ligands were tested in the rhodium catalyzed hydroformylation of 1-octene. The diethylamine substituted ligand 4a was found to be highly active, whereas 4bwas less reactive but revealed slightly better regioselectivity of 62\% under optimized conditions. Additionally, 4a and 4b were found to catalyze the hydroformylation of styrene, 1-undecenol and 1,1-disubstituted functional olefin, methyl methacrylate. Both the ligands displayed excellent conversion of styrene, and 4b revealed an excellent branch selectivity of 75\%. Although 1-undecenol proved to be amenable to hydroformylation (85-90\% conversion to aldehyde), both the ligands failed to discriminate between the linear and branched products. Substrate methyl methacrylate proved to be highly challenging and reduced conversion (between 33-42\%) was observed under optimized conditions. Ligand 4a was found to be highly selective towards linear aldehyde (81\% linear selectivity).},
	doi = {10.1007/s12039-017-1341-z},
	author = {Deshmukh, Satej S. and Gaikwad, Shahaji R. and Pandey, Swechchha and Mali, Pramod S. and Chikkali, Samir H.}
}
