Enantioselective tandem conjugate addition elimination reactions 2
... conditions 29 Chapter O O Br COR1 CH 3CN, rt + 1.5 eq 11h COR2 Entry 20 a-e 20 [R1, R2] 20 a[R1= R2= S COR R 2OC 21 a-e Product ] Time(hr) Yield/%a ee/%b 21 a 16 83 94 2c 20 a 21 a 21 74 94 3d 20 a 21 a 21 87 ... CH 2Cl2, rt 2eq Et 3N 29 a-k R O R P X P X R R SN2' type SN2 type Entry 29 , R X Time (hr) Yield%b Product 29 a, Ph O 17 SN2′ type 29 b, p-FPh O 23 SN2′ type 29 c,...
Ngày tải lên: 14/09/2015, 14:12
... Chapter 1. 1 Tandem conjugate addition- elimination (CA-E) reactions The SN2′ reaction (1) and the tandem conjugate addition- elimination reaction (2) which yields ... ee 11 K Fuji, M Node, H Nagasawa, Y Naniwa, T Taga, K Machida and G Snatzke, J Am Chem Soc., 19 89, 11 1, 79 21- 7925 12 R Tamura, K.-i Watabe, N Ono, Y Yamamoto, J Org Chem., 19 92, 57, 4895-4903 13 ......
Ngày tải lên: 14/09/2015, 14:12
... 40a 96 - 67 3: 1 39 b, 4-NO2 40b 27 47 54 5:1 39 c, 4-CN 40c 21 64 39 5:1 39 d, 4-CF3 40d 97 82 38 3: 1 39 e, 4-Cl 40e 24 31 47 2:1 39 f, 2-Cl 40f 96 35 47 3: 1 39 g, 3- Cl 40g 44 36 60 4:1 39 h, 3- Br 40h ... 11 32 42d, OBn 43d 16 93 40 42e, OCHPh2 43e 27 49 45 42f, OnBu 43f 75 31 7 42g, OtBu 43g 68 20 38 42h, OCH2CF3 43h 12 43 42i, CH3 43i 27 22 46 10 42j, Et 43j 26 20...
Ngày tải lên: 14/09/2015, 14:12
Enantioselective tandem conjugate addition elimination reactions 4
... ee%b Entry R 4- NO2 Me 56a 10 90 50 2c 4- NO2 Me 56a 12 89 54 3d 4- NO2 n Bu 56b 14 50 41 4- NO2 Bn 56c 89 48 3-NO2 Bn 56d 73 47 2-NO2 Bn 56e 72 14 4-CN Bn 56f 63 48 2-Cl-5-NO2 Bn 56g 82 31 a Isolated ... 2002, 1 14, 46 89 -46 92; Angew Chem Int Ed., 2002, 41 , 45 07 -45 10 (d) M Shi and J.-K Jiang, Tetrahedron: Asymmetry, 2002, 13, 1 941 -1 947 (e) M Shi, Y.-M Xu and Y.-L Shi,...
Ngày tải lên: 14/09/2015, 14:12
Enantioselective tandem conjugate addition elimination reactions 5
... 2 157 -2163 1 15 Chapter 13 C NMR (50 0 MHz, CDCl3, ppm) δ 25. 5, 25. 6, 25. 7, 29.1, 29.2, 45. 5, 73.1, 121.2, 122 .5, 1 25. 8, 129.3, 132 .5, 144.1, 147.4, 206.3; IR (film, cm-1) 3413, 1020, 2934, 153 2; ... 1H, J = 5. 8 Hz), 5. 62 (d, 1H, J = 5. 8 Hz), 5. 99 (s, 1H), 6.22 (s, 1H), 7 .53 (d, 2H, J = 8.7 Hz), 8.18 (d, 2H, J = 8.7 Hz); 13C NMR (300 MHz, CDCl3, ppm) δ 25. 5, 25. 6, 25. 7,...
Ngày tải lên: 14/09/2015, 14:12
Guanidine and guanidinium salt catalyzed enantioselective phosphorus carbon bond formation reactions 2
... CH2 Cl2 , -20 o C O 93a 122 H S O N O Ph 124 80% yield, 99% ee OH O OH OH R1 R2 122 MeOC O R2 124 OH H CO2 Me 124 a 92% yield 98% ee OH PhOC OH 114a (10 mol%) CH 2Cl2, -20 oC OH O O OH H CO2 Et ... (99%) 103d : R1=Ph; R 2= CN (97%) 103e : R 1=Ph; R2 =COPh (80%) 102a : R 1=R 2= CN 102b: R1=R2 =CO 2Me 102c: R 1=R 2= COPh 102d : R1=Ph; R 2= CN 102e : R 1=Ph; R2 =COPh O O Ph2 P(O)H TBD Ph Ph...
Ngày tải lên: 14/09/2015, 08:38
Pentanidium catalyzed enantioselective phase transfer reactions 2
... achieved (Scheme 2. 2) 32 Chapter Scheme 2. 1 Highly enantioselective Michael reactions of with catalyst 11 Scheme 2. 2 Organic-soluble base BEMP in phase- transfer system In 20 02, Arai et al developed ... Am Chem Soc 20 08, 130, 4897-4905 11 (a)Kano, T.; Kumano, T.; Maruoka, K Org Lett 20 09, 11, 20 23 20 25 (b) Wang, Y.; Kumano, T.; Kano, T.; Maruoka, K Org Lett 20 09, 11,...
Ngày tải lên: 09/09/2015, 17:53
Organocatalytic conjugate addition reactions
... Michael reactions of hydroxycarbamates 156a with different Michael acceptors List of Figures Fig 1.1 Publications for asymmetric organocatalytic conjugate additions and organocatalytic reactions ... quaternary ammonium catalyzed conjugate addition Scheme 1.2 Mukaiyama’s chiral quaternary ammonium phenoxide catalyzed conjugate addition in a tandem Mukaiyama-Michael addition...
Ngày tải lên: 16/10/2015, 15:35
36 pericyclic reactions 2 sigmatropic and electrocyclic reactions from organicchemistry clayden
Ngày tải lên: 13/04/2015, 15:23
Alpha fluorinated aromatic ketone as nucleophile in asymmetric organocatalytic c n and c c bonds formation reactions 2
... deprotonation/deuteriation process 2. 2 Enantioselective H/D exchange of -fluorinated aromatic ketones 2. 2.1 Synthesis of -fluorinated aromatic cyclic ketones and chiral bicyclic guanidine catalyst ... much (entries 12- 13) Table 2. 1 Optimization of the asymmetric H/D exchange reaction of -fluorinated ketone 82a in different conditions (Scheme 2. 6) incorporation en...
Ngày tải lên: 10/09/2015, 15:51
Design of a promoter to enhance the stability of catalysts for hydrocarbon reactions 2
... (Xu and Saeys, 20 06) have been proposed and shown to improve the stability of Ni catalysts The objective of this thesis is to design a promoter to enhance the stability of Ni-based catalysts Thermodynamic ... understanding of the elementary steps and the origin of catalyst promotion, as well as to the design of a new, improved catalyst Th...
Ngày tải lên: 11/09/2015, 16:06
Guanidine and guanidinium salt catalyzed enantioselective phosphorus carbon bond formation reactions 1
... Ph2CH 90 R /S 3 :1 86 :1 5 :1 55 :1 12 :1 54 :1 Scheme 1. 11 Ebetino’s asymmetric Michael addition of phosphinic and aminophosphinic acid An asymmetric Michael addition of phosphinic and aminophosphinic ... Adv Synth Catal 2004, 346, 10 35 10 50 Hiratake, J.; Oda, J., Biosci Biotech Biochem 19 97, 61, 211 – 218 Pietrusiewicz, K M.; Zablocka, M., Chem Rev 19 94, 94, 13 75 14 11...
Ngày tải lên: 14/09/2015, 08:38
Guanidine and guanidinium salt catalyzed enantioselective phosphorus carbon bond formation reactions 3
... Chapter 181a 56 30 ; 25 136 b [2-NpCH2] 181b 37 35 ; 15 136 c [3, 5-MeOC6H4CH2] 181c 58 32 ; 20 136 d [3- NO2C6H4CH2] 181d 58 36 ; 14 136 e [Et] 181e 45 38 ; 18 a 136 a [Bn] 136 f [i-Bu] 181f 48 56; 32 donor : ... 1:11 tBu F3 C F3C H N H N Ph Ph NH Ph CF3 CF3 BAr F-4 = B HN 2BAr F-4 Ph F3C CF3 F3 C 148 CF3 Scheme 3. 1 Göbel’s chiral bis(amidinium) salt 148 catalyzed Diels-Alder re...
Ngày tải lên: 14/09/2015, 08:38
Guanidine and guanidinium salt catalyzed enantioselective phosphorus carbon bond formation reactions 4
... - 34. 8 IR (KBr) 7 74, 15 04, 3050 cm-1 HRMS (ESI) m/z 44 0.1 348 (M+H+), calc for C28H24ClNP 44 0.1335 The ee of 147 was determined by converting back to 146 using H2O2 4. 6 Protocol for guanidinium salt ... 127.2, 127.3, 127 .4, 127.6, 127.9, 128.0, 129.3, 129.6, 129.7, 130.3, 132.9, 133.0, 133.3, 133 .4, 133.9, 1 34. 0, 1 34. 1, 1 34. 2, 1 34. 3, 1 34. 6, 1 34. 7, 137.8, 139.9, 142...
Ngày tải lên: 14/09/2015, 08:38
Chiral organometallic complexes promoted cycloaddition and insertion reactions 2
... 57(1) C (22 ) 404(3) 8 02( 2) 26 51 (2) 51(1) C (23 ) -989 (2) 20 01(3) 25 11 (2) 56(1) C (24 ) 3064 (2) 1 125 (2) 3 129 (1) 34(1) C (25 ) 27 07 (2) 7 72( 2) 3759 (2) 48(1) C (26 ) 25 32( 3) -25 0 (2) 3861 (2) 62( 1) C (27 ) 27 00(3) ... -936 (2) 3348 (2) 64(1) C (28 ) 30 52( 3) -603 (2) 27 31 (2) 58(1) C (29 ) 323 5 (2) 434 (2) 26 18(1) 42( 1) C(30) 423 9 (2) 28 96 (2) 35 52( 1) 30(...
Ngày tải lên: 16/09/2015, 15:54