114883-85-1Relevant academic research and scientific papers
CHEMOKINE RECEPTOR MODULATORS AND USES THEREOF
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Paragraph 1719-1720, (2018/05/03)
Disclosed herein, inter alia, are compounds and methods of use thereof for the modulation of chemokine receptor activity.
Exploring steric effects in diastereoselective synthesis of chiral aminophenolate zinc complexes and stereoselective ring-opening polymerization of rac-lactide
Wang, Haobing,Yang, Yang,Ma, Haiyan
supporting information, p. 7356 - 7372 (2016/08/06)
A series of tridentate chiral aminophenol proligands and corresponding zinc complexes, LZnX (L = (S)-2-{[(1-R4-2-pyrrolidinyl)CH2N(R3)-]CH2}-6-R1-4-R2-C6H2O, X = N(SiMe3)2, R3 = nBu, R4 = Bn: R1 = R2 = Cl (1), R1 = R2 = Me (2), R1 = R2 = tBu (3); X = N(SiMe3)2, R1 = trityl, R2 = Me: R3 = n-octyl, R4 = Bn (4), R3 = Bn, R4 = Bn (5), R3 = nBu, R4 = naphthalen-1-ylmethyl (6), R3 = nBu, R4 = iPr (7); R1 = R2 = cumyl, R3 = Et, R4 = Bn: X = N(SiMe3)2 (8), X = OtBu (9), X = Et (10), X = Cl (11)), have been synthesized. Complexes 4, 6, and 11 were obtained as enantiopure products (4 and 6 as enantiopure a; 11 as enantiopure b), while complexes 1-3, 5, and 7-10 as a pair of diastereomers, but in different ratios, which have been proved by X-ray diffraction and NMR spectroscopic studies. When exposed to the ring-opening polymerization of rac-lactide, most of these complexes can effectively produce PLAs with narrow polydispersities, desirable molecular weights, and moderate to high isotacticities. The structure-selectivity relationships, including the relationships of structure-synthesis diastereoselectivity and structure-polymerization stereoselectivity, have been further investigated. Consistent trends of diastereoselectivity and stereoselectivity are observed with the variations of the R1 group at the ortho-position of the phenolate ring and the R3 group in the pyrrolidinyl moiety. The decrease of the steric bulkiness of the R4 group on the central amine has less influence on the diastereoselectivity, but leads to considerable loss of the stereoselectivity, whereas the decrease of the steric bulkiness of the X group results in a reverse of the diastereoselectivity, but shows no influence on the stereoselectivity. There is probably no direct relationship between the diastereoselectivity in complex synthesis and the stereoselectivity of the complex toward the ROP of rac-LA. The stereocontrol of these complexes might largely rely on the substituents in the ligand framework rather than their diastereomer ratios.
Amidation of esters assisted by Mg(OCH3)2 or CaCl2
Bundesmann, Mark W.,Coffey, Steven B.,Wright, Stephen W.
experimental part, p. 3879 - 3882 (2010/08/19)
Magnesium methoxide (Mg(OCH3)2) and calcium chloride have been shown to facilitate the direct aminolysis of esters by ammonia to primary amides. Methyl, ethyl, isopropyl, and tert-butyl esters were converted to the corresponding carboxamides in good yields. Reactions have been run on a larger scale and without the safety liability inherent in the use of magnesium nitride (Mg3N2). Ammonium chloride and amine hydrochlorides have been used successfully in the place of ammonia with magnesium methoxide.
Strained azetidinium ylides: New reagents for cyclopropanation
Couty, Francois,David, Olivier,Larmanjat, Benedicte,Marrot, Jerome
, p. 1058 - 1061 (2008/02/05)
(Chemical Equation Presented) Azetidinium ylides showed a remarkable ability to perform the cyclopropanation of Michael acceptors. Ephedrine-derived azetidinium ylides allowed the formation of substituted cyclopropanes in good yields and at a high level o
Catalytic epoxidation of unfunctionalized alkenes by dinuclear nickel(II) complexes
Rispens, Minze T.,Gelling, Onko Jan,De Vries, Andre H.M.,Meetsma, Auke,Van Bolhuis, Fre,Feringa, Ben L.
, p. 3521 - 3546 (2007/10/03)
The synthesis, crystal and molecular structure and catalytic activity in epoxidation reactions of new dinuclear nickel(II)-complexes, octahedral μ-diacetato-μ-[2,6-bis[N-2-2'-pyridylethyl)formimidoyl]phenolato]bis nickel(II)·perchlorate·methanol (6) and square planar (μ-hydroxo-μ-[2,6-bis[N-((S)-1-benzyl-2-yl-pyrrolidine)formimidoyl]p henolato]bisnickel(II)·bisperchlorate (7), are described. For the preparation of 7 a new 5-step route for homochiral bisamine (S)-benzyl-2-aminomethyl-pyrrolidine (19) was developed starting from (S)-proline. Epoxidation of unfunctionalized alkenes with sodium hypochlorite and tert-butyl hydroperoxide as terminal oxidants was effectively catalyzed with bisnickel(II)-complexes 6 and 7, and a turnover of 165 was reached using trans-β-methylstyrene (34). The epoxidations probably proceed via a radical intermediate (such as OCl·) and no enantioselectivity is obtained under phase transfer conditions. In epoxidation reactions employing tert-butyl hydroperoxide as terminal oxidant a turnover of 43 was obtained with trans-stilbene (30) as substrate. Unexpectedly in the case of styrene (29) 1,2-bis-(tert-butylperoxy)ethylbenzene (59) was isolated as the major product.
TRANSITION METAL COMPLEXES - A NEW CLASS OF CATALYSTS OF INTERFACIAL ALKYLATION FOR THE ASYMMETRICAL SYNTHESIS OF α-AMINO ACIDS
Belokon', Yu. N.,Maleev, V. I.,Videnskaya, S. O.,Saporovskaya, M. B.,Tsyryapkin, V. A.,Belikov, V. M.
, p. 110 - 118 (2007/10/02)
A new class of catalysts of interfacial asymmetrical alkylation is suggested for the synthesis of α-amino acids - positively charged complexes of the transition metals Cu(II), Ni(II), and Pd(II).These complexes consist of several fragments, by variation of which the structure of the catalysts can readily be modified.The complexes are chiral on account of (S)proline derivatives contained in them as one of the fragments.The catalyst complexes (C) were used in alkylation of amino acid fragments of Ni(II) complexes of the Schiff base of glycine with N-(2-pyridinecarbonyl)-o-aminobenzophenone (Ni-PBP-Gly) and the Schiff base of alanine with N-(2-pyridinecarbonyl)-o-aminobenzaldehyde (Ni-PBA-Ala) under interfacial conditions.After decomposition of alkylated complexes, phenylalanine and α-methyl-phenylalanine were isolated with yields of 33-87percent and optical purity (o. p.) from 3 to 21percent, depending on the C used.
