844-40-6Relevant academic research and scientific papers
One-Pot and Reducible-Functional-Group-Tolerant Synthesis of α-Aryl- and α-Heteroaryl-α-Trifluoromethyl Alcohols via Tandem Trifluoroacetylation and MPV Type Reduction
Funabiki, Kazumasa,Hayakawa, Ayaka,Kani, Ryunosuke,Inuzuka, Toshiyasu,Kubota, Yashuhiro
, p. 5978 - 5984 (2019/08/30)
We have developed a new one-pot synthesis of α-aryl- and α-heteroaryl-α-trifluoromethyl alcohols carrying not only arenes with electron-withdrawing groups but also electron-deficient nitrogen-containing heteroarenes, which are of increasing interest becau
Efficient photolytic C-H bond functionalization of alkylbenzene with hypervalent iodine(iii) reagent
Sakamoto, Ryu,Inada, Tsubasa,Selvakumar, Sermadurai,Moteki, Shin A.,Maruoka, Keiji
supporting information, p. 3758 - 3761 (2016/03/25)
A practical approach to radical C-H bond functionalization by the photolysis of a hypervalent iodine(iii) reagent is presented. The photolysis of [bis(trifluoroacetoxy)iodo]benzene (PIFA) leads to the generation of trifluoroacetoxy radicals, which allows the smooth transformation of various alkylbenzenes to the corresponding benzyl ester compounds under mild reaction conditions.
Solvolytic reactivity of heptafluorobutyrates and trifluoroacetates
Denegri, Bernard,Kronja, Olga
experimental part, p. 5927 - 5933 (2009/12/26)
(Chemical Equation Presented) A series of X,Y-substituted benzhydryl heptafluorobutyrates (1-6-HFB) and trifluoroacetates (1-6-TFA) were subjected to solvolysis in various methanol/water, ethanol/water, and acetone/water mixtures at 25°C. The LFER equation log k = sf(Ef + N f) was used to derive the nucleofuge-specific parameters (N f and sf) for SN1-type reaction. In comparison with TFA, the HFB leaving group is a better nucleofuge for less than 0.5 unit of Nf. X,Y-Substituted benzhydryl trifluoroacetates solvolyze by way of SN1 reactions unless electron-withdrawing groups are attached to aromatic rings. In such cases the substrates solvolyze faster than predicted for the SN1 route because of the change in mechanism. X,Y-Substituted benzhydryl heptafluorobutyrates examined here (Ef ≥ -7.7) solvolyze according to the SN1 pathway. The almost parallel log k vs. Ef lines in various solvents for HFBs and TFAs, and the corresponding slope parameters (sf are in the range of 0.91 and 0.83), indicate early TS with moderately advanced charge separation. NBO charges of HFB and TFA anions and the affinities obtained, all calculated at the PCM-B3LYP/6-311+G(2d,p)//PCM-B3LYP/6-311+G(2d, p) level, revealed that the HFB anion slightly better delocalizes the developing negative charge than TFA, and that the affinity of the benzhydrylium ion is slightly larger toward TFA than toward the HFB anion, which is in accordance with the greater solvolytic reactivity of HFB.
Kinetics of the solvolyses of benzhydryl derivatives: Basis for the construction of a comprehensive nucleofugality scale
Denegri, Bernard,Streiter, Andre,Juric, Sandra,Ofial, Armin R.,Kronja, Olga,Mayr, Herbert
, p. 1648 - 1656 (2007/10/03)
A series of 21 benzhydrylium ions (diarylmethylium ions) are proposed as reference electrofuges for the development of a general nucleofugality scale, where nucleofugality refers to a combination of leaving group and solvent. A total of 167 solvolysis rate constants of benzhydrylium tosylates, bromides, chlorides, trifluoroacetates, 3,5-dinitrobenzoates, and 4-nitroben-zoates, two-thirds of which have been determined during this work, were subjected to a least-squares fit according to the correlation equation log k 25°C = Sf(Nf + Ef), where s f and Nf are nucleofuge-specific parameters and E f is an electrofuge-specific parameter. Although nucleofuges and electrofuges characterized in this way cover more than 12 orders of magnitude, a single set of the parameters, namely sf, Nf, and E f, is sufficient to calculate the solvolysis rate constants at 25°C with an accuracy of ± 16%. Because sf ≈ 1 for all nucleofuges, that is, leaving group/ solvent combinations, studied so far, qualitative discussions of nucleofugality can be based on Nf.
Zinc-Promoted Reactions. 1. Mechanism of the Clemmensen Reaction. Reduction of Benzophenone in Glacial Acetic Acid
Vona, Maria Luisa Di,Rosnati, Vittorio
, p. 4269 - 4273 (2007/10/02)
The mechanism of the Clemmensen reduction of diaryl ketones was investigated by reducing benzophenone, benzhydryl chloride, and dichlorodiphenylmethane in AcOH under a variety of conditions.Besides diphenylmethane, dimeric products were isolated that were indicative of the formation of radical species.Different product distributions were obtained from reactions run under different conditions.The reduction of deuteriated benzhydryl chloride was also performed.A quite complicated mechanistic pattern, involving ionic and nonionic reactions, emerged from the experimental p icture.Two pathways, connected through the protonated substrate, were recognized.According to the first pathway the reduction is promoted by a SET from Zn to the substrate, leading to the formation of a carbon radical having one zinc atom bound to the oxygen of the carbonyl group.Benzhydryl chloride, benzhydryl acetate, and dichlorodiphenylmethane are involved in the process.The product distributions suggest the occurrence of several SETs, which involve the formation of different radical species.Ionic reactions are responsible for the second route to the reduced products.Nucleophilic displacements also participate to the complex mechanism.
THE REACTIONS OF N-BENZOYLPEROXYCARBAMIC ACID WITH AZINES AND IMINES
Paredes, Rodrigo,Bastos, Holger,Montoya, Raul,Chavez, Alba Lucia,Dolbier, William R.,Burkholder, Conrad R.
, p. 6821 - 6830 (2007/10/02)
N-Benzoylperoxycarbamic acid (BPC) was found to react generally with imines and azines to form oxaziridines rather than N-oxides.The imine products were stable, but those found from azines apparently were unstable and converted to ketones or aldehydes plus diazo compounds.
O-DIPHENYLMETHYLATION OF ALCOHOLS AND CARBOXYLIC ACIDS USING DIPHENYLMETHYL DIPHENYL PHOSPHATE AS ALKYLATING AGENT
Kolovos, Miltiadis,Froussios, Cleanthis
, p. 3909 - 3912 (2007/10/02)
Diphenylmethyl diphenyl phosphate reacts quickly under mild conditions with various alcohols and carboxylic acids towards diphenyl-methyl ethers and esters respectively while hydroxyacids can be selectively alkylated at the alcohol site.
