Synthesis of cyclohexapyrrolizidines: C-methylation of vinylogous amides

1978 ◽  
Vol 56 (3) ◽  
pp. 320-325 ◽  
Author(s):  
Ronald B. Kelly ◽  
Sandra J. Alward
Keyword(s):  
Convenient Method ◽  
X Ray ◽  
X Ray Crystallography ◽  
Vinylogous Amides ◽  
High Yields

A synthesis of the cyclohexapyrrolizidines 32 and 33 is described; the structure of the latter was determined by X-ray crystallography. It is anticipated that this synthesis will serve as a model for the construction of a similar pyrrolizidine system during a projected synthesis of thelepogine 2.A convenient method for the C-methylation of cyclic vinylogous amides is also described. This procedure, which is similar to published procedures, affords high yields of methylated product and is regiospecific.

scholarly journals Silylated gallium and indium chalcogenide ring systems as potential precursors to ME (E=O, S) materials

2013 ◽  
Vol 11 (7) ◽  
pp. 1225-1238
Author(s):  
Iliana Medina-Ramírez ◽  
Cynthia Floyd ◽  
Joel Mague ◽  
Mark Fink
Keyword(s):  
Thermal Decomposition ◽  
Room Temperature ◽  
Membered Ring ◽  
Molecular Structures ◽  
Nmr Studies ◽  
X Ray ◽  
X Ray Crystallography ◽  
High Yields ◽  
Vt Nmr ◽  
State 1

AbstractThe reaction of R3M (M=Ga, In) with HESiR′3 (E=O, S; R′3=Ph3, iPr3, Et3, tBuMe2) leads to the formation of (Me2GaOSiPh3)2(1); (Me2GaOSitBuMe2)2(2); (Me2GaOSiEt3)2(3); (Me2InOSiPh3)2(4); (Me2InOSitBuMe2)2(5); (Me2InOSiEt3)2(6); (Me2GaSSiPh3)2(7); (Et2GaSSiPh3)2(8); (Me2GaSSiiPr3)2(9); (Et2GaSSiiPr3)2(10); (Me2InSSiPh3)3(11); (Me2InSSiiPr3)n(12), in high yields at room temperature. The compounds have been characterized by multinuclear NMR and in most cases by X-ray crystallography. The molecular structures of (1), (4), (7) and (8) have been determined. Compounds (3), (6) and (10) are liquids at room temperature. In the solid state, (1), (4), (7) and (9) are dimers with central core of the dimer being composed of a M2E2 four-membered ring. VT-NMR studies of (7) show facile redistribution between four- and six-membered rings in solution. The thermal decomposition of (1)–(12) was examined by TGA and range from 200 to 350°C. Bulk pyrolysis of (1) and (2) led to the formation of Ga2O3; (4) and (5) In metal; (7)–(10) GaS and (11)–(12) InS powders, respectively.

Heterometallische Cluster durch ligandunterstützte Metallfragmentkondensation / Heterometallic Clusters by Ligand Assisted Metal Fragment Condensation

1991 ◽  
Vol 46 (9) ◽  
pp. 1169-1176 ◽  
Author(s):  
Wolfgang Rohde ◽  
Gert Fendesak
Keyword(s):  
Double Bond ◽  
Chelate Complexes ◽  
Heterometallic Clusters ◽  
X Ray ◽  
X Ray Crystallography ◽  
Inert Solvent ◽  
Fragment Condensation ◽  
Olefinic Double Bond ◽  
High Yields ◽  
Iron Fragment

Dicobalt complexes of 3-vinylpropargylic alcohol derivatives react with biscyclooctenetricarbonyliron to give new chelate complexes of the iron tricarbonyl fragment with the olefinic double bond and the alcohol oxygen atom bound to the iron fragment. These compounds react upon heating in an inert solvent to give FeCo-alkynyl cluster complexes in high yields. One of these compounds has been structurally characterized by X-ray crystallography.

scholarly journals Neue Synthesewege zu neutralen gemischtsubstituierten Eisen-Schwefel-Clustern / Novel Synthetic Pathways to Neutral Mixed-Ligand Iron-Sulfur Clusters

1996 ◽  
Vol 51 (7) ◽  
pp. 1040-1048 ◽  
Author(s):  
M. Harmjanz ◽  
C. Junghans ◽  
U.-A. Opitz ◽  
B. Bahlmann ◽  
S. Pohl
Keyword(s):  
Elemental Sulfur ◽  
Large Excess ◽  
Iron Sulfur Clusters ◽  
Thiourea Derivatives ◽  
X Ray ◽  
X Ray Crystallography ◽  
Iron Sulfur ◽  
Neutral Ligands ◽  
High Yields ◽  
Sulfur Donor

The reaction of [Fe(NiSiMe3)2)2] with thiols RSH, elemental sulfur, and neutral ligands L (with sulfur donor atoms, e. g. thiourea derivatives) gives [Fe4S4(SR)2L2] clusters in high yields. The structure of [Fe4S4(2.4.6-(C3H7)3C6H2-S)2(dpdmi)2] (dpdmi: diisopropyldimethyl- imidazolthion) was determined by X-ray crystallography.When [Fe4S4I4]2- is reacted with a large excess of PMePh2 or PMe2Ph [F6S6I2(PMePh2)4] and [Fe6S6l2(PMe2Ph)4]. respectively, are obtained in nearly quantitative yield. Basket-like structures of the [Fe6S6]2+ cores were detected by X-ray structure analysis. While [Fe4S4(SR)4]2- clusters do not react with phosphanes at ambient temperature 2:2 functional­ized species like [Fe4S4(SR)2(tmtu)2] lead to basket-type clusters [Fe6S6(SR)2(PR3)4].

Activation of C–Cl Bonds: Synthesis and Structural Characterization of [Ru2(μ-Cl)(μ-PtBu2)(μ- Ph2PN(H)PPh2)(CO)4]

2013 ◽  
Vol 68 (5-6) ◽  
pp. 743-746 ◽  
Author(s):  
Tobias Mayer ◽  
Hans-Christian Böttcher
Keyword(s):  
Carbon Tetrachloride ◽  
Single Crystals ◽  
Structural Characterization ◽  
Title Compound ◽  
X Ray ◽  
X Ray Crystallography ◽  
High Yields

The synthesis and structural characterization of the complex [Ru2(μ-Cl)(μ-PtBu2)(μ-dppa)(CO)4] (4, dppa = Ph2PN(H)PPh2) are reported. The title compound and two other related complexes were obtained in high yields by the reaction of the coordinatively unsaturated species [Ru2(μ-H)(μ-PtBu2)(μ-PˆP)(CO)4] (PˆP = dppa, 3; PˆP =Ph2PN(Ph)PPh2, 5; PˆP =Ph2PN(CH2Ph)PPh2, 6) with carbon tetrachloride. Single crystals of 4 grown from dichloromethane-acetone have been analyzed by X-ray crystallography

Nano ZrO2: an efficient, recyclable, and inexpensive catalyst for diastereoselective three-component Mannich reactions

2014 ◽  
Vol 92 (7) ◽  
pp. 659-664 ◽  
Author(s):  
M. Saeed Abaee ◽  
Elahe Akbarzadeh ◽  
Abbas Shockravi ◽  
Mohammad M. Mojtahedi ◽  
Hamid Reza Khavasi
Keyword(s):  
Spectroscopic Data ◽  
Room Temperature ◽  
Aromatic Aldehydes ◽  
Significant Loss ◽  
Mannich Reactions ◽  
X Ray ◽  
X Ray Crystallography ◽  
Aniline Derivatives ◽  
High Yields ◽  
Acyclic Ketones

A facile procedure is developed for the three-component Mannich reactions of several heterocyclic, homocyclic, and acyclic ketones by using catalytic quantities of nano ZrO2. As a result, the starting ketones undergo rapid reactions with a variety of aromatic aldehydes and aniline derivatives at room temperature to produce stereoselectively high yields of the corresponding anti β-amino ketones. Interestingly, the catalyst could be recycled for several runs in a row without significant loss of its activity. The structure of the products was assigned based on their spectroscopic data and the anti stereoselectivity was confirmed by X-ray crystallography.

scholarly journals Efficient Preparation of Potassium Arylmethylene-4-(1H-Pyrazol-5-ol)-4′-(1H-Pyrazol-5-Olate) Derivatives via a Four-Component Reaction

2018 ◽  
Vol 42 (6) ◽  
pp. 313-316
Author(s):  
Ting Wang ◽  
Yang Yu ◽  
Xushun Qing ◽  
Chenlu Dai ◽  
Cunde Wang
Keyword(s):  
Potassium Carbonate ◽  
Reaction Conditions ◽  
X Ray ◽  
X Ray Crystallography ◽  
Broad Scope ◽  
Substituted Benzaldehydes ◽  
High Yields ◽  
Operational Simplicity

A four-component reaction was investigated to prepare potassium arylmethylene-4-(1 H-pyrazol-5-ol)-4′-(1 H-pyrazol-5-olate) derivatives from dialkyl but-2-ynedioates, phenylhydrazine, substituted benzaldehydes and potassium carbonate without any catalyst or promoter. The structure of a typical product was confirmed by X-ray crystallography. The advantages of the present methodology are efficiency, broad scope, operational simplicity, high yields and mild reaction conditions.

Synthesis and molecular structures of N,N-dialkyl-4-nitrosoaniline adducts of formally d6 metalloporphyrins of ruthenium and cobalt

2001 ◽  
Vol 05 (09) ◽  
pp. 702-707 ◽  
Author(s):  
LI CHEN ◽  
JESSE B. FOX ◽  
GEUN-BAE YI ◽  
MASOOD A. KHAN ◽  
GEORGE B. RICHTER-ADDO
Keyword(s):  
Solid State ◽  
Single Crystal ◽  
Molecular Structures ◽  
Spectroscopic Methods ◽  
X Ray ◽  
X Ray Crystallography ◽  
High Yields ◽  
Solid State Structures

Para-aminosubstituted nitrosoarenes react with Ru ( CO )( OEP ) or [ Co ( TPP )( THF )2] SbF 6 (OEP2- = 2,3,7,8,12,13,17,18-octaethylporphyrinato dianion, TPP2- = 5,10,15,20-tetraphenylporphyrinato dianion) to generate Ru ( OEP )( ONC 6 H 4 NMe 2)2 and [ Co ( TPP )( ONC 6 H 4 NR 2)2] SbF 6 ( R = Me , Et ), respectively, in fair to high yields. These N -bound nitrosoarene complexes have been characterized by spectroscopic methods. The complexes Ru ( OEP )( ONC 6 H 4 NMe 2)2 and [ Co ( TPP )( ONC 6 H 4 NMe 2)2] ClO 4 have also been characterized by single-crystal X-ray crystallography. Their structures represent the first reported solid-state structures of Ru and Co porphyrins containing C-nitroso ligands.

Straightforward route to γ-sultams via novel SN/Michael addition tandem

Synthesis ◽  
2020 ◽  
Author(s):  
Anastasiia Klochkova ◽  
Andrey Bubyrev ◽  
Dmitrii Viktorovich Dar'in ◽  
Olga Yu. Bakulina ◽  
Mikhail Krasavin ◽  
...  
Keyword(s):  
Transition Metal ◽  
Electronic Properties ◽  
Michael Addition ◽  
X Ray ◽  
Metal Free ◽  
X Ray Crystallography ◽  
High Yields

A novel tandem approach to trisubstituted γ-sultams has been developed involving N-alkylation of methanesulfonanilides with EWG-substituted allyl bromides followed by intramolecular Michael addition. A series of various isothiazolidine 1,1-dioxides has been prepared under mild transition metal-free conditions in high yields and trans-diastereoselectivity (confirmed by X-ray crystallography). The dependence of reactivity on electronic properties of substrates has been investigated.

Condensation of cis-9-methyl-2-decalone with cyclic β-amino esters: synthesis and X-ray crystallography of perhydroazacyclopentaanthracenes and perhydroazabenzanthracenes

1976 ◽  
Vol 54 (10) ◽  
pp. 1512-1520 ◽  
Author(s):  
Ronald B. Kelly ◽  
Barry A. Beckett ◽  
Ijaz Mumtaz ◽  
Eric Stanley ◽  
Peter S. White
Keyword(s):  
Carbon Atom ◽  
Crystallographic Analysis ◽  
Amino Ketone ◽  
Structural Isomers ◽  
X Ray ◽  
X Ray Crystallography ◽  
Amino Esters ◽  
Condensation Products ◽  
Vinylogous Amides ◽  
Pure Isomer

Condensation of cis-9-methyl-2-decalone, 9, with ethyl 2-pyrrolidineacetate, 10, afforded a mixture of two isomeric vinylogous amides, 11. Oxidation of either one pure isomer, 11a, or the mixture 11 to the same pyridone, 12, revealed that the two condensation products were stereoisomeric at a single carbon atom and not structural isomers. Reduction of 11a afforded the amino ketone 13. The structures assigned to 11, 12, and 13 are based on X-ray crystallographic analysis of 13.Similarly, condensation of 9 with ethyl 2-piperidineacetate, 14, afforded the isomers 15a and 15b both of which were oxidized to the same pyridone, 16. Reduction of 15a afforded 17. The structures assigned to 15, 16, and 17 are based on X-ray crystallographic analysis of 17.

scholarly journals Microwave-assisted efficient one-pot synthesis of N 2-(tetrazol-5-yl)-6-aryl/heteroaryl-5,6-dihydro-1,3,5-triazine-2,4-diamines

2020 ◽  
Vol 16 ◽  
pp. 1706-1712
Author(s):  
Moustafa Sherief Moustafa ◽  
Ramadan Ahmed Mekheimer ◽  
Saleh Mohammed Al-Mousawi ◽  
Mohamed Abd-Elmonem ◽  
Hesham El-Zorba ◽  
...  
Keyword(s):  
Microwave Heating ◽  
Aromatic Aldehydes ◽  
One Pot ◽  
X Ray ◽  
X Ray Crystallography ◽  
Microwave Assisted ◽  
One Pot Synthesis ◽  
High Yields

An efficient one-pot synthesis of N 2-(tetrazol-5-yl)-6-aryl/heteroaryl-1,3,5-triazine-2,4-diamine derivatives was developed by reacting 5-amino-1,2,3,4-tetrazole with aromatic aldehydes and cyanamide in pyridine under controlled microwave heating with high yields. X-ray crystallography confirmed the structure of the obtained products.

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