There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

Name Sequence Exon 2 mG6pc S 5’-TCCCTGTCACCTGTGAG-3’ Exon 5 mG6pc AS 5’-CACAAGAAGTCTTTGTAA-3’ Exon1 mG6pcS 5’-TTACCAAGACTCCCAGGACTG-3’ Exon2 mG6pcAS 5’-GAGCTGTTGCTGTAGTAGTCG-3’ Pck1S 5’-AGCCTTTGGTCAACAACTGG-3’ Pck1AS 5’-TGCCTTCGGGGTTAGTTATG-3’ GcgR S 5’-ACCCAACTATTGCTGGTTGC-3’ GcgR AS 5’-CCATGTTGTCATTGCTGGTC-3’ Hmgcs2 S 5’-CCGTATGGGCTTCTGTTCAG-3’ Hmgcs2 AS 5’-AGCTTTGTGCGTTCCATCAG-3’ mL19S 5’-AGAAGATTGACCGCCATAT-3’ mL19AS 5’-TTCGTGCTTCCTTGGTCTTAGA-3’ CRU G6pc S 5’-TTTGCTATTTTACGTAAATCACCCT-3’  CRU G6pc AS 5’-GTACCTCAGGAAGCTGCCA-3’ CRU Pck1 S 5’-GGCCTCCCAACATTCATTAAC-3’ CRU Pck1 AS 5’-GTAGCTAGCCCTCCTCGCTTTAA-3’ GRU G6pc S 5’-CACCCCTTAGCACTGTAAGCCGTGTG-3’ GRU G6pc AS 5’-GGATTCAGTCTGTAGGTCAACCTAGCCC-3’ GRU Pck1 S 5’-TGCAGCCAGCAACATATGAA-3’

Supplementary table 1

IN the preface to this volume Prof. Hammett truly says: “It is one of the commonest occurrences in the development of science that the necessary subdivision of the subject leads to a temporary neglect of phenomena lying on the borders between specialised fields.” Fortunately, both in Great Britain and in the United States this extreme specialization has not prevented chemists from recognizing that fundamental physical theories are quite as applicable to problems in organic chemistry as they are to studies of the simpler inorganic compounds. Chemical studies of reaction mechanisms can have little value unless they are developed from basic theories of molecular structure and statistical thermodynamics. These have been summarized logically in the first third of this volume and thereafter have been applied to the quantitative consideration of the majority of the well-known reactions of organic chemistry. Physical Organic Chemistry: Reaction Rates, Equilibria and Mechanisms. By Prof. Louis P. Hammett. (International Chemical Series.) Pp. x + 404. (New York and London: McGraw-Hill Book Co., Inc., 1940.) 26s.

Physical Organic Chemistry

Decarboxylative functionalization of α,β-unsaturated carboxylic acids is an emerging area that has been developed significantly in recent years. This critical review focuses on the different decarboxylative functionalization reactions of cinnamic acids leading to the formation of various C–C and C–heteroatom bonds. Apart from metal carboxylates, decarboxylation in cinnamic acids has been achieved efficiently under metal-free conditions, particularly via the use of hypervalent iodine reagents. We believe this review will encourage organic chemists to develop vinylic decarboxylation in a more appealing way with an understanding of new mechanistic insight.

Decarboxylative functionalization of cinnamic acids

Several palladium−phosphinous acids have been prepared and employed in cross-coupling reactions of aryl or acyl halides with aliphatic and aromatic organozinc reagents. The POPd7-catalyzed reaction of aryl halides, including electron-rich aryl chlorides, and arylzinc reagents was found to afford biaryls exhibiting alkoxy, alkylthio, amino, ketone, cyano, nitro, ester, and heteroaryl groups in 75−93% yield. Excellent results were obtained with sterically hindered substrates which gave di- and tri-ortho-substituted biaryls in up to 92% yield. Aryl halides also undergo POPd7-catalyzed aryl−vinyl and aryl−alkyl bond formation under mild conditions. Styrenes and alkylarenes were prepared in 79−93% yield from aryl halides and vinyl or alkylzinc reagents. The replacement of aryl halides by acyl halides provides access to ketones which were produced in up to 98% yield when POPd was used as catalyst. This approach overcomes the limited substrate scope, reduced regiocontrol, and low functional group tolerance of tr...

Palladium-phosphinous acid-catalyzed cross-coupling of aryl and acyl halides with aryl-, alkyl-, and vinylzinc reagents.

Metal nitrate driven nitro Hunsdiecker reaction with α,β-unsaturated carboxylic acids under solvent-free conditions

Poly ethylene glycols (PEG-200, 400, 600, 4000 and 6000) supported reactions were conducted with certain α, β-unsaturated acids in presence of metal nitrates under solvent free (solid state) and mineral acid free conditions. The reactants were ground in a mortar with a pestle for about 30 minutes. The aromatic acids underwent nitro decarboxylation and afforded β-nitro styrene derivatives in very good yield while α, β-unsaturated aliphatic carboxylic acids gave corresponding nitro derivatives. Addition of PEG accelerated rate of the reaction enormously. Reaction times substantially decreased from several hours to few minutes followed by highly significant increase in the product yield. Among the several PEGs PEG-300 has been found to be much more effective than other PEGs.

/pdf/poly-ethylene-glycols-as-efficient-media-for-the-synthesis-32hsmfykiu.pdf

Poly Ethylene Glycols as Efficient Media for the Synthesis of β-Nitro Styrenes from α, β-Unsaturated Carboxylic Acids and Metal Nitrates under Conventional and Non-Conventional Conditions

Kinetics of oxidation of xanthine alkaloids, such as Xanthine (XAN), hypoxanthine (HXAN), caffeine (CAF), theophylline (TPL), and theobromine (TBR), have been studied with ceric ammonium nitrate (CAN) using poly ethylene glycols (PEG) as catalysts. Reaction obeyed first order kinetics in both [CAN] and [Xanthine alkaloid]. Highly sluggish CAN-xanthine alkaloid reactions (in acetonitrile media even at elevated temperatures) are enhanced in presence PEGs (PEG-200, -300, -400, -600). An increase in [PEG] increased the rate of oxidation linearly. This observation coupled with a change in absorption of CAN in presence of PEG, [H–(OCH2–CH2)n–O–NH4Ce(NO3)4(CH3CN)] (PEG bound CAN species), is considered to be more reactive than CAN. The mechanism of oxidation in PEG media has been explained by Menger-Portnoy’s enzymatic model.

/pdf/polyethylene-glycols-as-efficient-catalysts-for-the-1wzdfeyvou.pdf

Polyethylene Glycols as Efficient Catalysts for the Oxidation of Xanthine Alkaloids by Ceric Ammonium Nitrate in Acetonitrile: A Kinetic and Mechanistic Approach

Hunsdiecker reactions with α,β-unsaturated carboxylic acids were conducted under solvent-free conditions in the presence of a few drops of HNO 3 together with a variety of metal nitrates [Mg(NO 3 ) 2 , Sr(NO 3 ) 2 ], Al(NO 3 ) 3 , Ca(NO 3 ) 2 , Ni(NO 3 ) 2 , Cd(NO 3 ) 2 , Zn(NO 3 ) 2 , Hg(NO 3 ) 2 , AgNO 3 , ZrO(NO 3 ) 2 , UO 2 (NO 3 ) 2 , Th(NO 3 ) 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.

Metal Nitrate Driven Nitro Hunsdiecker Reaction with α,β-Unsaturated Carboxylic Acids under Solvent-Free Conditions.

Polyethylene glycols (PEGs) were found to be efficient media for decarboxylative nitration of α,β-unsaturated aromatic carboxylic acids by ceric ammonium nitrate (CAN) in acetonitrile to give β-nitrostyrene derivatives. Kinetics of the reaction exhibited second order kinetics with a first order dependence on [CAN] and [substrate]. Reactions were too sluggish to be studied in the absence of PEG; therefore detailed kinetics were not taken up. Reaction times were reduced from 24 hrs to few hours. The catalytic activity was found to be in the increasing order PEG-300 > PEG-400 > PEG-600 > PEG-200. Mechanism of PEG-mediated reactions was explained by Menger-Portnoy's scheme as applied in micellar kinetics.

/pdf/polyethylene-glycols-as-efficient-media-for-decarboxylative-ndp6u6i8pq.pdf

Polyethylene Glycols as Efficient Media for Decarboxylative Nitration of α,β-Unsaturated Aromatic Carboxylic Acids by Ceric Ammonium Nitrate in Acetonitrile Medium: A Kinetic and Mechanistic Study

K. Ramesh

Papers

Metal nitrate driven nitro Hunsdiecker reaction with α,β-unsaturated carboxylic acids under solvent-free conditions

Poly Ethylene Glycols as Efficient Media for the Synthesis of β-Nitro Styrenes from α, β-Unsaturated Carboxylic Acids and Metal Nitrates under Conventional and Non-Conventional Conditions

Polyethylene Glycols as Efficient Catalysts for the Oxidation of Xanthine Alkaloids by Ceric Ammonium Nitrate in Acetonitrile: A Kinetic and Mechanistic Approach

Metal Nitrate Driven Nitro Hunsdiecker Reaction with α,β-Unsaturated Carboxylic Acids under Solvent-Free Conditions.

Polyethylene Glycols as Efficient Media for Decarboxylative Nitration of α,β-Unsaturated Aromatic Carboxylic Acids by Ceric Ammonium Nitrate in Acetonitrile Medium: A Kinetic and Mechanistic Study