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Anh Cổ Thanh Thiện, đã lấy bằng PhD ở South Korea, hiện nay đang công tác tại Viện Khoa học Vật liệu Ứng Dụng TpHCM. Anh Thiện ủng hộ 5 bài báo cho Thư viện ChemVN. BM cho các bài báo vào folder Hoá Xúc tác nhé.

1, 1,2-Ferrocenediylazaphosphinines 3: A New Class of Planar Chiral Ligands for Cu-Catalyzed Cyclopropanation

Seung Hwan Paek, Thanh-Thien Co, Dong Ho Lee, Yu Chul Park, and Tae-Jeong Kim

Bull. Korean Chem. Soc. 2002, Vol. 23, No. 12, 1702

Abstract:

The synthesis and catalytic application of a new class of planar chiral ferrocenes, 1,2-ferrocenediylazaphosphinines (1 and 2) are described. They are powerful ligands for the copper(I)-catalyzed asymmetric cyclopropanation of a range of alkenes with diazo esters to exhibit an exceptionally high degree of diastereoselectivity (~100% de) in favor of trans isomers, regardless the structure of the olefins and the diazo compounds. Comparative studies between 1 and 2 reveal that the former works better in terms of
diastereocontrol. In contrast, however, enantioselectivity is low with both 1 and 2 as a whole although, in certain cases with a proper combination of the olefin and the diazo ester, high optical yields (up to 100% ee) can be achieved. Other reaction parameters such as the reaction temperature and the structure of the ligand do exhibit some influence, although infinitestimal, on both chemical and optical yields.

2, Chiral [Iminophosphoranyl]ferrocenes: Synthesis, Coordination Chemistry, and Catalytic Application

Thanh Thien Co, Sang Chul Shim, Chan Sik Cho, Dong-Uk Kim, and Tae-Jeong Kim

Bull. Korean Chem. Soc. 2005, Vol. 26, No. 9, 1359

Abstract:

A series of new chiral [iminophosphoranyl]ferrocenes, {η5-C5H4-(PPh2=N-2,6-R2-C6H3)}Fe{η5-C5H3-1-PPh2-2-CH(Me)NMe2} (1: R = Me, iPr), {η5-C5H4-(PPh2=N-2,6-R21-C6H3)}Fe{η5-C5H3-1-(PPh2=N-2,6-R2-C6H3)-2-CH(Me)R2} (2: R1 = Me, Pr; R2 = NMe2, OMe), and (η5-C5H5)Fe{η5-C5H4-1-PR2-2-CH(Me)N=PPh3} (3:R = Ph, C6H11) have been prepared from the reaction of [1,1'-diphenylphosphino-2-(N,N-dimethylamino) ethyl]ferrocene with arylazides (1 & 2) and the reaction of phosphine dichlorides (R3PCl2) with [1,1'- diphenylphosphino-2-aminoethyl]ferrocene (3), respectively. They form palladium complexes of the type [Pd(C3H5)(L)]BF4 (4-6: L = 1-3), where the ligand (L) adopts an η2-N,N (2) or η2-P,N (3) as expected. In the case of 1, a potential terdentate, an η2-P,N mode is realized with the exclusion of the ?P=NAr group from the coordination sphere. Complexes 4-6 were employed as catalysts for allylic alkylation of 1,3-diphenylallyl acetate leading to an almost stoichiometric product yield with modest enantiomeric excess (up to 74% ee). Rh(I)-complexes incorporating 1-3 were also prepared in situ for allylic alkylation of cinnamyl acetate as a probe for both regio- and enantioselectivities of the reaction. The reaction exhibited high regiocontrol in favor of a linear achiral isomer regardless of the ligand employed.

3, Chiral (iminophosphoranyl)ferrocenes: highly efficient ligands for rhodium- and iridium-catalyzed enantioselective hydrogenation of unfunctionalized olefins

Thanh Thien Co and Tae-Jeong Kim

Chem.Commun., 2006, 3537–3539

Abstract:

A series of chiral (iminophosphoranyl)ferrocenes (1–3) are highly efficient ligands for Rh- and Ir-catalyzed hydrogenation of a number of unfunctionalized olefins; almost perfect
enantiomeric excesses (up to 99% ee) have been achieved under mild reaction conditions.

4, 1,2-Ferrocenediylazaphosphinines: An Unusual Coordination Behavior and Application to Allylic Alkylation

Thanh Thien Co, Seung Whan Paek, Sang Chul Shim, Chan Sik Cho, and Tae-Jeong Kim

Organometallics 2003, 22, 1475 - 1482

Abstract:

The reaction of 1,2-ferrocenediylazaphosphinines (1a, R1 = H; 1b, R1 = Me; 1c, R1 = Ph) with M(CO)6 (M = Mo, W), MX(CO)5 (M = Mn, Re; X = Br, Cl), and [Pd(3-C3H5)Cl]2 shows a strong tendency to adopt an unusual chelating bidentate coordination through nitrogen and the carbonyl oxygen, yielding M(2-N,O)(CO)4 (2, M = Mo; 3, M = W), M(2-N,O)(X)(CO)3 (6, M = Mn, X = Br; 7, M = Re, X = Cl), and [Pd(2-N,O)(3-C3H5)]BF4 (after treatment with AgBF4) (8), respectively. X-ray crystallographic structure determinations of 3a (R1 = H) and 8a (R1 = H) show the formation of a five-membered metallacycle with the distance of the metal-carbonyl oxygen bond being shorter than that of the metal-nitrogen bond in both compounds. The complexes 2 and 3 further undergo oxidative addition with allyl iodide to yield the corresponding M(II) complexes of the type [M(2-N,O)( 3-C3H5)(I)(CO)2] (4, M = Mo; 5, M = W). Complexes 2-5 and 8 were employed as catalysts for nucleophilic allylic substitution of allyl acetates as a probe for both regio- and enantioselectivities of the reaction. All reactions involving unsymmetrical allyl acetates (E)-RCH=CHCH2OAc (R = Pr, Ph) led exclusively to the formation of achiral linear product (E)-RCH=CHCH2Nu regardless of the type of catalysts, the ligand, or the allyl substrate employed. One exception to the above statement is the observation that Mo- and W-based catalysts (2-5) are totally inactive toward the allylic substitution of cinnamyl acetate (R = Ph). Asymmetric allylic alkylation of a symmetrically 1,3-disubstituted substrate, PhCH=CHCH(OAc)Ph, is accomplished only by Pd-catalysts (8) with enantiomeric excesses up to 50% ee.

5, Chiral (Iminophosphoranyl)ferrocenes: A New Class of Practical Ligands for Rhodium-Catalyzed Asymmetric Hydrogenation

Thanh Thien Co, Sang Chul Shim, Chan Sik Cho, and Tae-Jeong Kim

Organometallics, 24 (20), 4824 -4831, 2005

Abstract:

A series of new chiral (iminophosphoranyl)ferrocenes, {5-C5H4-(PPh2=N-2,6-R2-C6H3)}Fe{5-C5H3-1-PPh2-2-CH(Me)(Y)} (1a, Y = NMe2, R = Me; 1b, Y = NMe2, R = iPr; 1c, Y = OMe, R = iPr), {5-C5H4-(PPh2=N-2,6-R2-C6H3)}Fe{5-C5H3-1-(PPh2=N-2,6-R2-C6H3)-2-CH(Me)(Y)} (2a, R = Me, Y = NMe2; 2b, R = iPr, Y = NMe2,; 2c, R = Me, Y = OMe), and (5-C5H5)Fe{5-C5H4-1-PR2-2-CH(Me)N=PPh3} (3a, R = Ph; 3b, R = C6H11), have been prepared from the reaction of 1,1'-bis(diphenylphosphino)-2-[(dimethylamino)ethyl]ferrocene with aryl azides (1 and 2) and the reaction of phosphine dichlorides (R3PCl2) with 1,1'-bis(diphenylphosphino)-2-(aminoethyl)ferrocene (3), respectively. They form rhodium complexes of the type [Rh(NBD)(L)]ClO4 (4-6; L = 1-3), where the ligand (L) adopts an 2(N,N) (2) or 2(P,N) mode (3), as expected. In the case of 1, a potential tridentate species, however, a chelating bidentate mode through the -CH(Me)NMe2 and -PPh2 groups is realized with the exclusion of the -P=NAr group from the coordination sphere, as confirmed by the X-ray crystal structure of [Rh(NBD)(1b)]ClO4 (4b). The new ligands (1-3) exhibit exceptionally high enantioselectivity (up to 99%) and catalytic activity in the Rh-catalyzed asymmetric hydrogenation of (E)-2-methylcinnamic acid, (Z)-2-acetamidocinnamate, and (Z)-2-acetamidoacrylate.