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Search for "cis–trans selectivity" in Full Text gives 4 result(s) in Beilstein Journal of Organic Chemistry.
N-tert-Butanesulfinyl imines in the asymmetric synthesis of nitrogen-containing heterocycles
- Joseane A. Mendes,
- Paulo R. R. Costa,
- Miguel Yus,
- Francisco Foubelo and
- Camilla D. Buarque
Beilstein J. Org. Chem. 2021, 17, 1096–1140, doi:10.3762/bjoc.17.86
- diastereoselectivities were observed with less bulky methyl 2-bromo-2-butenoate (R2 = CH3CH=), leading to an almost complete loss of cis/trans selectivity by the reaction with aliphatic aldimines 14. The absolute configuration of the reaction products was unambiguously determined after X-ray crystallographic analysis of
- some of the reaction products. In order to rationalize the observed stereochemical outcome, a six-membered cyclic transition state has been proposed. The addition to imine 14 with SS configuration takes place on the less hindered Re face, on the other hand, the cis/trans selectivity observed being a
Graphical Abstract
Scheme 1: General strategy for the enantioselective synthesis of N-containing heterocycles from N-tert-butane...
Scheme 2: Methodologies for condensation of aldehydes and ketones with tert-butanesulfinamides (1).
Scheme 3: Transition models for cis-aziridines and trans-aziridines.
Scheme 4: Mechanism for the reduction of N-tert-butanesulfinyl imines.
Scheme 5: Transition models for the addition of organomagnesium and organolithium compounds to N-tert-butanes...
Scheme 6: Synthesis of 2,2-dibromoaziridines 15 from aldimines 14 and bromoform, and proposed non-chelation-c...
Scheme 7: Diastereoselective synthesis of aziridines from tert-butanesulfinyl imines.
Scheme 8: Synthesis of vinylaziridines 22 from aldimines 14 and 1,3-dibromopropene 23, and proposed chelation...
Scheme 9: Synthesis of vinylaziridines 27 from aldimines 14 and α-bromoesters 26, and proposed transition sta...
Scheme 10: Synthesis of 2-chloroaziridines 28 from aldimines 14 and dichloromethane, and proposed transition s...
Scheme 11: Synthesis of cis-vinylaziridines 30 and 31 from aldimines 14 and bromomethylbutenolide 29.
Scheme 12: Synthesis of 2-chloro-2-aroylaziridines 36 and 32 from aldimines 14, arylnitriles 34, and silyldich...
Scheme 13: Synthesis of trifluoromethylaziridines 39 and proposed transition state of the aziridination.
Scheme 14: Synthesis of aziridines 42 and proposed state transition.
Scheme 15: Synthesis of 1-substituted 2-azaspiro[3.3]heptanes, 1-phenyl-2-azaspiro[3.4]octane and 1-phenyl-2-a...
Scheme 16: Synthesis of 1-substituted 2,6-diazaspiro[3.3]heptanes 48 from chiral imines 14 and 1-Boc-azetidine...
Scheme 17: Synthesis of β-lactams 52 from chiral imines 14 and dimethyl malonate (49).
Scheme 18: Synthesis of spiro-β-lactam 57 from chiral (RS)-N-tert-butanesulfinyl isatin ketimine 53 and ethyl ...
Scheme 19: Synthesis of β-lactam 60, a precursor of (−)-batzelladine D (61) and (−)-13-epi-batzelladine D (62)...
Scheme 20: Rhodium-catalyzed asymmetric synthesis of 3-substituted pyrrolidines 66 from chiral imine (RS)-63 a...
Scheme 21: Asymmetric synthesis of 1,3-disubstituted isoindolines 69 and 70 from chiral imine 67.
Scheme 22: Asymmetric synthesis of cis-2,5-disubstituted pyrrolidines 73 from chiral imine (RS)-71.
Scheme 23: Asymmetric synthesis of 3-hydroxy-5-substituted pyrrolidin-2-ones 77 from chiral imine (RS)-74.
Scheme 24: Asymmetric synthesis of 4-hydroxy-5-substituted pyrrolidin-2-ones 80 from chiral imines 79.
Scheme 25: Asymmetric synthesis of 3-pyrrolines 82 from chiral imines 14 and ethyl 4-bromocrotonate (81).
Scheme 26: Asymmetric synthesis of γ-amino esters 84, and tetramic acid derivative 86 from chiral imines (RS)-...
Scheme 27: Asymmetric synthesis of α-methylene-γ-butyrolactams 90 from chiral imines (Z,SS)-87 and ethyl 2-bro...
Scheme 28: Asymmetric synthesis of methylenepyrrolidines 92 from chiral imines (RS)-14 and 2-(trimethysilylmet...
Scheme 29: Synthesis of dibenzoazaspirodecanes from cyclic N-tert-butanesulfinyl imines.
Scheme 30: Stereoselective synthesis of cyclopenta[c]proline derivatives 103 from β,γ-unsaturated α-amino acid...
Scheme 31: Stereoselective synthesis of alkaloids (−)-angustureine (107) and (−)-cuspareine (108).
Scheme 32: Stereoselective synthesis of alkaloids (−)-pelletierine (112) and (+)-coniine (117).
Scheme 33: Synthesis of piperidine alkaloids (+)-dihydropinidine (122a), (+)-isosolenopsin (122b) and (+)-isos...
Scheme 34: Stereoselective synthesis of the alkaloids(+)-sedamine (125) from chiral imine (SS)-119.
Scheme 35: Stereoselective synthesis of trans-5-hydroxy-6-substituted-2-piperidinones 127 and 129 from chiral ...
Scheme 36: Stereoselective synthesis of trans-5-hydroxy-6-substituted ethanone-2-piperidinones 132 from chiral...
Scheme 37: Stereoselective synthesis of trans-3-benzyl-5-hydroxy-6-substituted-2-piperidinones 136 from chiral...
Scheme 38: Stereoselective synthesis of trans-5-hydroxy-6-substituted 2-piperidinones 139 from chiral imine 138...
Scheme 39: Stereoselective synthesis of ʟ-hydroxypipecolic acid 145 from chiral imine 144.
Scheme 40: Synthesis of 1-substituted isoquinolones 147, 149 and 151.
Scheme 41: Stereoselective synthesis of 3-substituted dihydrobenzo[de]isoquinolinones 154.
Scheme 42: Enantioselective synthesis of alkaloids (S)-1-benzyl-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline (...
Scheme 43: Enantioselective synthesis of alkaloids (−)-cermizine B (171) and (+)-serratezomine E (172) develop...
Scheme 44: Stereoselective synthesis of (+)-isosolepnosin (177) and (+)-solepnosin (178) from homoallylamine d...
Scheme 45: Stereoselective synthesis of tetrahydroquinoline derivatives 184, 185 and 187 from chiral imines (RS...
Scheme 46: Stereoselective synthesis of pyridobenzofuran and pyridoindole derivatives 193 from homopropargylam...
Scheme 47: Stereoselective synthesis of 2-substituted 1,2,5,6-tetrahydropyridines 196 from chiral imines (RS)-...
Scheme 48: Stereoselective synthesis of 2-substituted trans-2,6-disubstituted piperidine 199 from chiral imine...
Scheme 49: Stereoselective synthesis of cis-2,6-disubstituted piperidines 200, and alkaloid (+)-241D, from chi...
Scheme 50: Stereoselective synthesis of 6-substituted piperidines-2,5-diones 206 and 1,7-diazaspiro[4.5]decane...
Scheme 51: Stereoselective synthesis of spirocyclic oxindoles 210 from chiral imines (RS)-53.
Scheme 52: Stereoselective synthesis of azaspiro compound 213 from chiral imine 211.
Scheme 53: Stereoselective synthesis of tetrahydroisoquinoline derivatives from chiral imines (RS)-214.
Scheme 54: Stereoselective synthesis of (−)-crispine A 223 from chiral imine (RS)-214.
Scheme 55: Synthesis of (−)-harmicine (228) using tert-butanesulfinamide through haloamide cyclization.
Scheme 56: Stereoselective synthesis of tetraponerines T1–T8.
Scheme 57: Stereoselective synthesis of phenanthroindolizidines 246a and (−)-tylophorine (246b), and phenanthr...
Scheme 58: Stereoselective synthesis of indoline, tetrahydroquinoline and tetrahydrobenzazepine derivatives 253...
Scheme 59: Stereoselective synthesis of (+)-epohelmin A (258) and (+)-epohelmin B (260) from aldimine (RS)-79.
Scheme 60: Stereoselective synthesis of (−)-epiquinamide (266) from chiral aldimine (SS)-261.
Scheme 61: Synthesis synthesis of (–)-hippodamine (273) and (+)-epi-hippodamine (272) using chiral sulfinyl am...
Scheme 62: Stereoselective synthesis of (+)-grandisine D (279) and (+)-amabiline (283).
Scheme 63: Stereoselective synthesis of (−)-epiquinamide (266) and (+)-swaisonine (291) from aldimine (SS)-126....
Scheme 64: Stereoselective synthesis of (+)-C(9a)-epi-epiquinamide (294).
Scheme 65: Stereoselective synthesis of (+)-lasubine II (298) from chiral aldimine (SS)-109.
Scheme 66: Stereoselective synthesis of (−)-epimyrtine (300a) and (−)-lasubine II (ent-302) from β-amino keton...
Scheme 67: Stereoselective synthesis of (−)-tabersonine (310), (−)-vincadifformine (311), and (−)-aspidospermi...
Scheme 68: Stereoselective synthesis of (+)-epohelmin A (258) and (+)-epohelmin B (260) from aldehyde 313 and ...
Scheme 69: Total synthesis of (+)-lysergic acid (323) from N-tert-butanesulfinamide (RS)-1.
2-Methyl-2,4-pentanediol (MPD) boosts as detergent-substitute the performance of ß-barrel hybrid catalyst for phenylacetylene polymerization
- Julia Kinzel,
- Daniel F. Sauer,
- Marco Bocola,
- Marcus Arlt,
- Tayebeh Mirzaei Garakani,
- Andreas Thiel,
- Klaus Beckerle,
- Tino Polen,
- Jun Okuda and
- Ulrich Schwaneberg
Beilstein J. Org. Chem. 2017, 13, 1498–1506, doi:10.3762/bjoc.13.148
- environment of the catalyst by introducing sterically demanding amino acids in the protein cavity [13]. Additionally, FhuA ΔCVFtev is stable over the time. As reported by Hayashi and co-workers, the polymerase based on nitrobindin loses structural integrity after 12 hours, resulting in a loss of cis/trans
- selectivity [13]. The membrane protein FhuA ΔCVFtev in MPD shows stability for more than three days under the reaction conditions and therefore is leading to significantly increased yields. Conclusion In conclusion, we successfully demonstrated the use of MPD as small-molecule stabilizer for utilization of
Graphical Abstract
Figure 1: Phenylacetylene polymerization of FhuA ΔCVFtev [29] refolded in a polymer or small amphiphilic molecule...
Figure 2: Hydrophobic transmembrane region of FhuA ΔCVFtev [29] stabilized by ≈200 MPD molecules. MPD is illustra...
Scheme 1: Coupling of [Rh]-1 to the open channel protein FhuA ΔCVFtev. SDS, sodium dodecyl sulfate; THF, tetr...
Figure 3: Circular dichroism spectra of 2 refolded in 2-methyl-2,4-pentanediol (MPD, red) and polyethylene–po...
Figure 4: MALDI–TOF mass spectra of apo FhuA ΔCVFtev (red; calculated m/z = 5902.6; found: m/z = 5911.7) and 2...
Application of cyclic phosphonamide reagents in the total synthesis of natural products and biologically active molecules
- Thilo Focken and
- Stephen Hanessian
Beilstein J. Org. Chem. 2014, 10, 1848–1877, doi:10.3762/bjoc.10.195
- butenolide 83 in hand the stage was set for one of the key steps of the synthesis. Addition of the anion of phosphonamide 28c to 83 proceeded with a high level of facial and cis/trans-selectivity to afford adduct 88 as a single diastereomer with the correct stereochemistry. Removal of the chiral auxiliary by
Graphical Abstract
Figure 1: Examples of phosphonamide reagents used in stereoselective synthesis.
Figure 2: Natural products and bioactive molecules synthesized using phosphonamide-based chemistry (atoms, bo...
Scheme 1: Olefination with cyclic phosphonamide anions, mechanistic rationale, and selected examples 27a–d [18].
Scheme 2: Asymmetric olefination with chiral phosphonamide anions and selected examples 31a–d [1,22].
Scheme 3: Synthesis of α-substituted phosphonic acids 33a–e by asymmetric alkylation of chiral phosphonamide ...
Scheme 4: Asymmetric conjugate additions of C2-symmetric chiral phosphonamide anions to cyclic enones, lacton...
Scheme 5: Asymmetric conjugate additions of P-chiral phosphonamide anions generated from 40a and 44a to cycli...
Scheme 6: Asymmetric cyclopropanation with chiral chloroallyl phosphonamide 47, mechanistic rationale, and se...
Scheme 7: Asymmetric cyclopropanation with chiral chloromethyl phosphonamide 28d [59].
Scheme 8: Stereoselective synthesis of cis-aziridines 57 from chiral chloroallyl phosphonamide 47a [62].
Scheme 9: Synthesis of phosphonamides by (A) Arbuzov reaction, (B) condensation of diamines with phosphonic a...
Figure 3: Original and revised structure of polyoxin A (69) [24-26].
Scheme 10: Synthesis of (E)-polyoximic acid (9) [24-26].
Figure 4: Key assembly strategy of acetoxycrenulide (10) [41,42].
Scheme 11: Total synthesis of (+)-acetoxycrenulide (10) [41,42].
Scheme 12: Synthesis squalene synthase inhibitor 19 by asymmetric sulfuration (A) and asymmetric alkylation (B...
Figure 5: Key assembly strategy of fumonisin B2 (20) and its tricarballylic acid fragment 105 [45,46].
Scheme 13: Final steps of the total synthesis of fumonisin B2 (20) [45,46].
Figure 6: Selected examples of two subclasses of β-lactam antibiotics – carbapenems (111 and 112) and trinems...
Scheme 14: Synthesis of tricyclic β-lactam antibiotic 123 [97].
Scheme 15: Total synthesis of (−)-anthoplalone (8) [56].
Figure 7: Protein tyrosine phosphatase (PTP) inhibitors 130, 131 and model compounds 16, 132 and 133 [68].
Scheme 16: Synthesis of model PTP inhibitors 16a,b [68].
Scheme 17: Synthesis of aziridine hydroxamic acid 17 as MMP inhibitor [63].
Scheme 18: Synthesis of methyl jasmonate (11) [48].
Figure 8: Structures of nudiflosides A (137) and D (13) [49].
Scheme 19: Total synthesis of the pentasubstituted cyclopentane core 159 of nudiflosides A (151) and D (13) an...
Figure 9: L-glutamic acid (161) and constrained analogues [57,124].
Scheme 20: Stereoselective synthesis of DCG-IV (162) [57].
Scheme 21: Stereoselective synthesis of mGluR agonist 21 [124].
Figure 10: Key assembly strategy of berkelic acid (15) [43].
Scheme 22: Total synthesis of berkelic acid (15) [43].
Figure 11: Key assembly strategy of jerangolid A (22) and ambruticin S (14) [27,28].
Scheme 23: Final assembly steps in the total synthesis of jerangolid A [27].
Scheme 24: Key assembly steps in the total synthesis of ambruticin S (14) [28].
Figure 12: General steroid construction strategy based on conjugate addition of 212 to cyclopentenone 48, exem...
Scheme 25: Total synthesis of estrone (12) [44].
The intriguing modeling of cis–trans selectivity in ruthenium-catalyzed olefin metathesis
- Naeimeh Bahri-Laleh,
- Raffaele Credendino and
- Luigi Cavallo
Beilstein J. Org. Chem. 2011, 7, 40–45, doi:10.3762/bjoc.7.7
- Petrochemical Institute (IPPI), P.O. Box 14965/115, Tehran, Iran 10.3762/bjoc.7.7 Abstract In this study we have investigated computationally the origin of the cis–trans selectivity in the Ru-catalyzed cross metathesis (CM) of a prototype monosubstituted olefin, i.e., propene. Our calculations suggest that the
- origin of the preferential formation of trans-olefins is in the product release step, which prevents the initially formed cis-olefin from escaping the metal, and returns it to the reaction pool until the trans-olefin is formed. Keywords: cis–trans selectivity; cross metathesis; DFT calculations; olefin
- reactive monosubstituted olefins are the minimization of homodimers and a control over the cis–trans selectivity, see Scheme 1. While minimization of homodimers can be achieved with proper handling of the reaction protocol [15], controlling the cis–trans selectivity is much more complicated, and is usually
Graphical Abstract
Scheme 1: Possible products resulting from the CM of terminal olefins.
Scheme 2: Representation of the reactions investigated.
Figure 1: Reaction profile for the formation of cis- and trans-2-butene.
