TMSCl imidazole DMF. Ph Ph OTMS. Michael reaction. Michael reaction Ph R 3. epoxidation O R
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1 eaction using diarylprolinol silyl ether derivatives as catalyst 1) C Et K C 3, ) MgBr, TF TMS hexane, 0 o C TBS p- C 6 4, T C Et 85%, 99% ee Angew. Chem., nt. Ed., 44, 41 (005). rg. Synth., 017, 94, 5. K TMS imidazole DMF ayashi Lab. omepage Development of new reactions Asymmetric reaction using amino acid or their derivatives as a catalyst, environmental conscious asymmetric reaction using water as a solvent, and research about origin of chirality Tandem Michael / enry reaction TMS This catalyst is synthesized in short steps from proline. Substituents on aryl and silyl moiety are easily modified. Excellent enantioselectivity is obtained TMS C, T TF, T TMS mol% 90%, 95% ee rg. Lett., 9, 5307 (007). C Diels-Alder reaction 1 α-benzoyloxylation Michael / cyclization reaction, T 3 TBS p- C 6 4, T 84%, 9% ee Angew. Chem., nt. Ed., 45, 6853 (006). C i Bu p- C 6 4, T C exo : endo = 80 : 0, 97% ee (exo) rg. Lett, 9, 859 (007). Angew. Chem., nt. Ed., 47, 6634 (008). toluene, 0 o C = 3,5-( 3 ) C TBS TF, T TBS Michael / aza enry / aminal formation / additional reaction TMS mol% 1 3 up to >90% de Chem. Asian. J., 4, 46 (009). 78%, 9% ee Chem. Commun,, 3083 (009). 63%, 95% ee Tetrahedron, 66, 4894 (010). Formal aza [33] cycloaddition Boc Formal carbo [33] cycloaddition / isomerization epoxidation 66%, 99% ee Angew. Chem., nt. Ed., 46, 49 (007). TBS Boc Boc (C ), 70 o C α β 90%, 94% ee, α : β = 34 : 66 Angew. Chem., nt. Ed., 47, 401 (008). TMS C, T Michael / enry / acetal formation / additional reaction C TBS C, T ac 3 rg. Lett., 11, 45 (009)., T a b, a : b = 9 : 1 rg. Lett., 11, 4056 (009). hexane, T Si 0 mol% rg. Lett., 1, 5434 (010). TMS toluene, T s 1,4-dioxane ; evapo Ti 4 C TMS s 1 TMS toluene, T ; evapo TMS 3 DBU Ti 4 C C 1 3 Single diastereomer rg.lett., 1, 4588 (010). Single diastereomer Angew. Chem., nt. Ed., 50, 3774 (011).
2 eaction using diarylprolinol silyl ether derivatives as catalyst 1 Ts Bz S 1 = alkyl or aryl Ts S 1 TMS p- C 6 4C TF, 4 o C TMS = 3,5-( 3) C 6 3- Ts ac 3 1,4-dioxane or brine, 10 o C 1 Chem. Eur. J., 17, 873 (011). = 3,5-( 3) C 6 3- Bz 87%, 98% ee Angew. Chem., nt. Ed., 47, 9053 (008). TMS ac 3 = 3,5-( 3) C 6 3- ab 4 Ts 1,4-dioxane, T Chem. Eur. J., 17, 873 (011). J. Synth. rg. Chem., Jpn., 014, 7, 18. TMS 10-0 mol% or, T 1 Et 3 3 = or up to 94% ee Chem. Eur. J. 0, 107 (014). Formal C- insertion 3 1 [6] cycloaddition reaction toluene, T TMS TMS 0 mol% DDQ TF aac TMS 1,4-dioxane, T (1,4-Addition versus 1,6-Addition) Angew. Chem., nt. Ed., 50, 390 (011). Adv. Synth. Catal. 355, 3661 (013). 75%, 96% ee Angew. Chem., nt. Ed., 47, 47 (008). Si, T : 0 ChemCatChem, 4, 959 (01). <eview> ChemCatChem, 5, 3499 (013). Concerted chanism J. Am. Chem. Soc., 133, 0175 (011). 3 1 TMS 0 mol% i Pr/, T ab 4 up to 94% ee Chem. Eur. J. 0, (014). Epoxydation Si toluene, T ab 4 up to 98% ee ChemCatChem, 7, 155 (015). Formal [3] cycloaddition Cyclopropanation Diels-Alder reaction TMS p- C 6 4 ab 4 C or C, T Si --imidazole Br C, T TMS 4 5 mol%, 0 C Eur. J. rg. Chem. 015, 430. Eur. J. rg. Chem. 015, = 3,5-( 3) C 6 3- C C up to exo : endo = 88 : 1 Chem. Eur. J. 016,, TMS C Et 1 C Et C toluene, T 1 up tp 99% ee Chem. Lett., 018, 47, 833. Aldol reaction C Et n polymer form TMS S 1 Et TF, T 1 = 3,5-( 3) -C 6 3- syn Diels-Alder reaction = 3,5-( 3) C 6 3- TMS 3C 0 mol% C, -0 C Domino Michael-aldol reaction 15 mol% Si Et 1 anti ( 1 < ) up to syn : anti = 1 :.9 up to 91% ee Eur. J. rg. Chem. 015, C C up to exo : endo = 99 : 1 up to 91% ee Chem. Eur. J. 016,, TMS C, i Pr, rt up to >99% ee dr = >95 : 5 Angew. Chem. nt. Ed. 017, 56, mol%, p-nitrophenol Et C Et/toluene, T ; 3PCC Et 96% ee syn : anti = 15 : 1 Angew. Chem. nt. Ed. 57, 1958 (018).
3 Aldol reaction by diarylprolinol as a catalyst C Et K C Et TF MgBr Et K Diarylprolinol This catalyst is synthesized in short steps from proline. This is effective organocatalyst of direct, enantioselective aldol reaction. Excellent enantioselectivity is obtained. DMF, 4 C ab 8%, 98% ee Angew. Chem., nt. Ed., 47, 08 (008). 3 MP, 4 C ab 56%, 8% ee rg. Lett., 10, 5581 (008). TPS C C DMF, 4 C C TPS =, 73%, 85% ee = Br, 86%, 8% ee Br Br ent-convolutamydine E ahalffragmentof Madindoline A and B CPC-1 rg. Lett., 11, 3854 (009). Et C Polymer form C Et n aq C Et C P=CC Bu, PPTS Et C C Bu Et C rg. Lett., 1, 966 (010). P=CC Et C Et K C C Et 40 wt% in water TF, T C(), Ts K C Angew. Chem., nt. Ed., 50, 804 (011). Et n 10% Et P=CC Et toluene, T C Et up to 96% ee Synlett, 485, (011). 40 wt% in water P=CC Et TF, T C Et Chem. Commun., 48, 4570 (01). DMF/, T Ts C() Chem. Lett. 4, 194 (013). 39 wt% in water P=CC Et TF, T C Et Et C ChemCatChem., 5, 883 (013). P=CC Et 1,4-dioxane/ T C Et ChemCatChem., 5, 887 (013). 37 wt% in water toluene/ 5 C P=CC Et C Et Chem. Lett. 43, 556 (014).
4 3 C Aldol reaction by diarylprolinol as a catalyst eaction catalyzed by proline Direct catalytic enantioselective α-aminoxylation = Three-Component Cross- of aldehydes = slow addition DMF, 0 o C slow addition C C 3 C, -0 o C quant, 98% ee Tetrahedron Lett., 44, 893 (003). eaction by proline-derived catalyst C 0 mol% toluene, T TF/, T ab 4 ab 4 C MP, -0 o C 3 C 99% ee CuS 4 5 (cat), 0 o C C 90%, 98% ee anti : syn = 1 : >95 3 C(=) cat. Tf Et 1) TBDPS imidazole ) Ms TMEDA 79%, >99% ee 87% Angew. Chem., nt. Ed., 43, 111 (004). J. rg. Chem., 69, 1548 (004). 3 C Aldol reaction 1 Ac 96% ee syn/anti = 1 : >0 Ms TBDPS Aldol / acetalization reaction Angew. Chem., nt. Ed., 4, 3677 (003). Adv. Synth. Catal., 347, 1604 (005). ature Protocols,, 113 (007). eaction by siloxyproline catalyst u - Base C n BuLi Li C DMF, -0 o C u C DMF, T TMSC p-ts 1 C u C Et Ac up to anti : syn = >0 : 1 Adv. Synth. Catal. 356, 3106 (014). u = F, 3, 4--C 6 4 up to 96% ee syn/anti = >0 : 1 ChemCatChem. 7, 1646 (015) TBDPS 98% ee 3 P=CC Et TBDPS 98% ee Adv. Synth. Catal. 358, 345 (016). rg. Lett. 10, 1445 (008). C S 3 C MP, 0 o C eaction by cystein-derived catalyst 3 C eaction by prolinate salt catalyst α-aminoxylation = TPS C J. rg. Chem., 7, 6493 (007). C acetone, 0 o C quant, 99% ee cis : trans = 8.3 : 1 J. Am. Chem. Soc., 17, 1608 (005). C K mol% C, 0 C ab 4, 0 C C K MP, -0 C L-proline 3 h, 90%, 98% ee proline K salt 4 h, 99%, 99% ee rg. Lett. 19, 4155 (017). ab 4 L-proline proline K salt TPS PMP 0 h, syn:anti = 5:1, 9% ee 5 h, syn:anti = 9:1, 99% ee rg. Lett. 0, 391 (018). α-aminoxylation TBS = C This catalyst is more reactive than proline. L-proline 4 h, <5% Siloxy proline h, 50%, 99% ee L-proline 0 h, <5% Siloxy proline 0 h, 63%, 96% ee Adv. Synth. Catal., 346, 1435 (004).
5 rganic solvent free reaction "in the water" or "in the presence of water"? rganic solvent free Dry and Wet condition asymetric aldol reaction with proline catalyst aldehyde-aldehyde neat C (cat.) in water in the presence of water "in water" : The participating reactions are dossplved homogeneously in water. "in the presence of water" : The reaction proeeds in a concentrated organic phase with water present as a second phase that influences the reactoin in the former. Angew. Chem. nt. Ed. 47, 634 (008). aldehyde-ketone C (cat.) water (3 eq.) anti : syn =upto14 :1 anti : syn = up to >0 :1 up to >99% ee ntermolecular aldol reaction between aldehydes in the presence of water Chem. Commun. 957 (007). ydrophobic part C ydrophilic part ab water, 0 C 97%, 99% ee anti/ syn = 19 : 1 Angew. Chem. nt. Ed. 45, 557 (006). rganic solvent free asymmetrric aldol reaction between ketone and aldehyde water phase C organic phase rganic solvent-free aldol reaction (40 ml) T, 4 h (3.8 ml) 7.9 ml (70 mmol) 9.3 ml (105 mmol) C.4 g ().5 g silica gel Filtration (60 ml AcEt) 3.8 ml (3 eq.) days 7.4 g (1 eq.) 13.7 g ( eq.) TBDPS C 59 mg (1 mol%) Distillation 16.4 g (94%) anti : syn =1.4:1 96% ee Self aldol reaction of propanal in water - reaction in water with proline-amide catalyst water C (cat.) Distillation 10 g (70%) anti : syn = 10 : 1 >99% ee rganic solvent free asymmetrric with proline catalyst TBDPS Angew. Chem. nt. Ed. 45, 958 (006). Chem. Eur. J. 13, 1046 (007). water, 0 C Effect of water on aldol reaction with 0 proteinogenic amino acid positive water effect 0 proteinogenic aminoacid () DMS and aq. DMS PMP 93%, 95% ee syn : anti =4.6:1 rg. Lett. 10, 1 (008). <5-89%, 0-96% ee anti : syn = : 1 Gly, Ala, Val, Leu, le, e, Trp, Pro, Ser, Thr, Tyr, Cys, t, is, Lys, g, Asp, Asn, Glu, Gln (.64 g, 0 mmol) (4.7 ml, 60 mmol) 5mol% TMS high enantioselectivity Chem. Commun. 54 (007). rganic solvent free asymmetric Diels-Alder reaction with proline derived catalyst water 10 ml water T, 8 h decantation then distillation C exo :endo=8:18 3. g, 81% 97% ee Angew. Chem. nt. Ed. 47, 634 (008). Synlett 1565 (006).
6 Application of igh Pressure lnduced by Water-Freezing to the direct catalytic asymmetric reaction Proposed mechanism of The novel method of high pressure by water-freezing: The high pressre (cat. 00 MaPa) is easilly is essily achieved simply by freesing water (-0 C) in a sealed autoclave. TMS toluene C cat. TMS Aldol reaction Tetrahedron Lett., 45, 4353 (004). esearch about of chirality Chem. Lett., 96 (00). 1 atm, T 00 atm, -0 C 0%, -% ee 99%, 96% ee J. Am. Chem. Soc., 15, 1108 (003). Baylis-illman reaction Tetrahedron Lett., 43, 8683 (004). TMS TMS TMS (E)-enamine C C 3 1) stirred for 4 h 0 C C C ) filtration prepared 10% ee (L-proline excess) Amplification of ee from initial low ee 99% ee (L) solution The key to find out origin of chirality Angew. Chem., nt. Ed. 45, 4593 (006). The effect of silyl substituents of diphenylprolinol silyl ether TMS Pot ecomomy : eview TMS elv. Chim. Acta, 94, 719 (011). elv. Chim. Acta, 96, 799, (013). β-e-face β-e-face e-face α β α β = Si 3, Si u - β-si-face β-si-face Si-face E Chem. Eur. J. 0, (014). Type A Type B Type C The different reactivity of diphenylprolinol silyl ether and diarylprolinol silyl ether TBS Michael type TES cycloaddition type Two-Pot Synthesis of Chiral 1,3-syn-Diols C C Chem. Eur. J. 1, 1337 (015). 16 A B C 3 1 ne-pot reaction A B C pot economy Chem. Sci. 7, 866 (016). The 16 / 18 exchanges existance in secondary amine catalyzed reactions TMS 16 cat cat TMS ; 1 3 P=CC 3 cat. Bi(Tf) 3 a 4 up to 98% ee up to syn : anti = >0 : 1 Chem. Eur. J. 018, 4, or 1 1 << TMS ,4-asymmetric induction using Cobalt alkyne complex MM MM Co (C) 8 MM 3 ZnLi ( 3 C)Co Co(C) 3 ( 3 C)Co Co(C) 3 up to anti:syn = 16:1 exchenge of oxygen is greatly faster than. So, it is impossible to determine the reaction proceeds with enol or enamine by containing of 18 of TM. Chem. Eur. J. 016,, MM Co (C) 8 MM ab4 MM ( 3 C)Co Co(C) 3 ( 3 C)Co Co(C) 3 up to anti:syn = 1:3 rganometallics 008, 7, 163.
7 tal-free oxidative transformations using ef reaction using molecular i BuK 1 C 3C 1 rt up to 95% Proposed chanism 1 1 eadily available base SET 1 xidative amidation of primary nitroalkane and amine or S K C 3 rt 1 Sterically demanding oxidative amidation of α-substituted malononitriles with amines C C 1 3 C 4 Boc C (1 eq.) ( eq.) 3 Cs C 3 Broad scope Minimal waste Autoinductive oxidation of α,α-diiodonitroalkanes 1 1 C 4 3 o epimerization (1 atm) (1 eq.), K C 3 ( eq.) toluene/tf (1:1, 0.1 M) rt, 0 h Boc 1 3 up to 96 % 68% 1 - Proposed chanism Chem. Eur. J. 0, (014). -= ' ' base base X (X = or ) C Angew. Chem. nt. Ed. 54, 1986 (015). Chem. Eur. J., 5538 (016). C C (1 eq.) ( eq.) (1 atm) Cs C 3 ( eq.) 4Å MS (100 mg) C 3 C (0.1 M) 50 C, 8 h - 90% Angew. Chem. nt. Ed. 55, 9060 (016). - (cat.) also work as catalyst iodide ' [] (cat.) auto ' catalysis Chem. Commun., 018, 54, 6360.
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