High-yield, regiospecific bis-functionalization of C70 using a Diels–Alder reaction in molten anthracene

2014 ◽  
Vol 50 (73) ◽  
pp. 10584-10587 ◽  
Author(s):  
Venkata S. Pavan K. Neti ◽  
Maira R. Cerón ◽  
A. Duarte-Ruiz ◽  
Marilyn M. Olmstead ◽  
Alan L. Balch ◽  
...  
Keyword(s):  
Single Crystal ◽  
Thermal Gravimetric Analysis ◽  
Alder Reaction ◽  
Diels Alder ◽  
High Yield ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diels Alder Reaction

A regiospecific bis-adduct of C70 with anthracene was prepared with unusually high yield (68%) by the Diels–Alder reaction in the absence of solvent (melt). The structure of the bis-adduct was an unexpected 12 o'clock isomer, as determined by single crystal X-ray diffraction, thermal gravimetric analysis (TGA) and spectroscopy.

Molecular Topology of Linked Anthracenes: X-Ray Structure Analyses of Alkyl Di-9-anthryl-glycolates, 9-Anthryl 9-Anthrylmethyl Ethers and Their Photoisomers

1989 ◽  
Vol 42 (11) ◽  
pp. 1869 ◽  
Author(s):  
HD Becker ◽  
BW Skelton ◽  
AH White
Keyword(s):  
Single Crystal ◽  
Alder Reaction ◽  
Diels Alder ◽  
Molecular Structures ◽  
Molecular Topology ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diels Alder Reaction ◽  
Photochemical Isomerization ◽  
Spatial Demand

The molecular structures of ethyl di-9-anthrylglycolate (1) and methyl di-9-anthrylglycolate (2), as well as those of three isomerization products of (2), have been established by single-crystal X-ray diffraction studies. In both (1) and (2), the anthracenemoieties are characterized by marked deviations from planarity. The stereospecific course of the thermal and photochemical isomerization of (2) by Diels -Alder reaction is suggested to be governed by the spatial demand of the alkoxycarbonyl group. Base-catalysed isomerization of (2) by migration of 9-anthryl from carbon to oxygen is associated with steric relief.

scholarly journals Cooperativity in the Reaction of 9-Methylanthracene With a 1,4-Dithiin Molecule

2014 ◽  
Vol 70 (a1) ◽  
pp. C913-C913
Author(s):  
Sanaz Khorasani ◽  
Manuel Fernandes
Keyword(s):  
Charge Transfer ◽  
Solid State ◽  
Single Crystal ◽  
Lattice Energy ◽  
Alder Reaction ◽  
Diels Alder ◽  
Reaction Products ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diels Alder Reaction

Solid-state chemistry involves the manipulation of molecules and materials through photochemical, thermal, or mechanical reaction methods. Single-crystal-to-single-crystal (SCSC) reactions are rare, but offer the opportunity to study reaction mechanisms and molecular motions in the solid state at the atomic level using single crystal X-ray diffraction. This allows the effect of the surrounding molecules, and hence the reaction cavity, on the reacting molecules to be examined which may ultimately lead to postcrystallization methods for creating new materials or reaction products that cannot easily be obtained via solution. SCSC reactions involving two different molecules are relatively uncommon. A convenient system that allows the study of such reactions is the [4+2] Diels-Alder reaction of 1,4-dithiintetracarboxylic type compounds with anthracene derivatives. In the work reported here, electron donor to acceptor interactions between 9-Methylanthracene and bis(N-cyclobutylimino)-1,4-dithiin lead to the formation of chiral charge transfer (CT) crystals [1]. These undergo a topochemical thermal SCSC [4 + 2] Diels-Alder reaction in the solid state. CT crystals were reacted at 400C, their structures determined by X-ray diffraction at various degrees of conversion, and examined using Hirshfeld surfaces and lattice energy calculations to find evidence of reaction cooperativity and feedback mechanisms. In this case, a maximum reaction conversion of around 96% was obtained indicating that the reaction is non-random within the charge transfer stacks, with close contacts between product molecules in the reacted crystal also providing some evidence for reaction cooperativity along the b axis perpendicular to the CT stacking axis.

scholarly journals Utilization of cajuput (Melaleuca leucadendron) twigs and sugarcane (Saccharum officinarum) bagasse agricultural waste for cellulose acetate production by environmentally friendly approach

2021 ◽  
Author(s):  
Roni Maryana ◽  
Muryanto Muryanto ◽  
Eka Triwahyuni ◽  
Oktaviani Oktaviani ◽  
Hafiizh Prasetia ◽  
...  
Keyword(s):  
Cellulose Acetate ◽  
Thermal Gravimetric Analysis ◽  
Agricultural Waste ◽  
Environmentally Friendly ◽  
Saccharum Officinarum ◽  
Hydroxyl Groups ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
X Ray

Abstract This study was carried out to investigate the extraction of cellulose acetate (CA) from cajuput (Melaleuca leucadendron) twigs and sugarcane (Saccharum officinarum) bagasse using an environmentally friendly method. At first, cellulose was extracted from cajuput twigs (CT) and sugarcane bagasse (SB) through prehydrolysis followed by soda (NaOH) pulping and elementary chlorine-free (ECF) bleaching. Later, the extracted cellulose was acetylated using iodine (I) as a catalyst. The obtained CA was characterized by Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), thermal gravimetric analysis (TGA), scanning electron microscope (SEM) and X-ray diffraction. FTIR and NMR analysis proved the replacement of free OH (hydroxyl) groups by acetyl groups. The degree of substitution (DS) showed the acetylation capability of cellulose extracted from CT and SB as well. The cellulose diameter and its crystallinity index were measured by SEM and X-ray diffraction, respectively. Furthermore, the thermal gravimetric analysis showed that CA extracted from CT and SB was thermal resistance. Therefore, CT and SB could be potential alternative resources for CA production using the mentioned method.

scholarly journals Extraction of Cellulose Acetate From Cajuput (Melaleuca leucadendron) Twigs and Sugarcane (Saccharum officinarum) Bagasse by Environmentally Friendly Approach

2021 ◽  
Author(s):  
Roni Maryana ◽  
Muryanto Muryanto ◽  
Eka Triwahyuni ◽  
Oktaviani Oktaviani ◽  
Hafiizh Prasetia ◽  
...  
Keyword(s):  
Cellulose Acetate ◽  
Thermal Gravimetric Analysis ◽  
Environmentally Friendly ◽  
Crystallinity Index ◽  
Saccharum Officinarum ◽  
Hydroxyl Groups ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
X Ray

Abstract This study was carried out to investigate the extraction of cellulose acetate (CA) from cajuput (Melaleuca leucadendron) twigs and sugarcane (Saccharum officinarum) bagasse using an environmentally friendly method. At first, cellulose was extracted from cajuput twigs (CT) and sugarcane bagasse (SB) through prehydrolysis followed by soda (NaOH) pulping and elemental chlorine-free (ECF) bleaching. Later, the extracted cellulose was acetylated using iodine (I) as a catalyst. The obtained CA was characterized by Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), thermal gravimetric analysis (TGA), scanning electron microscope (SEM) and X-ray diffraction. FTIR and NMR analysis proved the replacement of free OH (hydroxyl) groups by acetyl groups. The degree of substitution (DS) showed the acetylation capability of cellulose extracted from CT and SB as well. The diameter of CA and its crystallinity index (CrI) were measured by SEM and X-ray diffraction, respectively. The diameter of CA extracted from CT was approximately 10 μm and it was approximately 20 to 30 μm for SB. The CrI of the CA extracted from SB and CT was 75.6 and 60.2, respectively. Furthermore, the thermal gravimetric analysis showed that CA extracted from CT and SB was thermal resistance. Therefore, CT and SB will be potential alternative resources for CA production using the mentioned medthod.

STUDY ON DECOMPOSITION OF GOETHITE/SIDERITE IN THERMAL MODIFICATION THROUGH XRD, SEM AND TGA MEASUREMENTS

2014 ◽  
Vol 21 (01) ◽  
pp. 1450019 ◽  
Author(s):  
SHAOXIAN SONG ◽  
FEIFEI JIA ◽  
CHANGSHENG PENG
Keyword(s):  
Thermal Gravimetric Analysis ◽  
Intermediate Phase ◽  
Thermal Modification ◽  
Experimental Results ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
X Ray ◽  
Decomposition Processes ◽  
Electronic Microscope

The decomposition of goethite and goethite/siderite concentrates into hematite with thermal modification was studied through the measurements of X-ray diffraction (XRD), scanning electronic microscope (SEM) and thermal gravimetric analysis (TGA). The experimental results showed that goethite decomposed into hematite directly at around 300°C without any intermediate phase and the decomposition of siderite completed at 500°C. Nanoscale granular structures were observed in the thermally treated products. It deserves highlighting that the decomposition processes proceeded from surfaces into bulks.

Two novel Diels-Alder adducts from Hippocratea celastroides roots and their insecticidal activity

2000 ◽  
Vol 78 (2) ◽  
pp. 248-254 ◽  
Author(s):  
M Jiménez-Estrada ◽  
R Reyes-Chilpa ◽  
S Hernández-Ortega ◽  
E Cristobal-Telésforo ◽  
L Torres-Colín ◽  
...  
Keyword(s):  
Alder Reaction ◽  
Diels Alder ◽  
X Ray Diffraction ◽  
Stored Grain ◽  
X Ray ◽  
Diels Alder Reaction ◽  
Antifeeding Activity ◽  
Hippocratea Celastroides ◽  
Stored Grain Insects

Two novel compounds, celastroidine A (1) and B (2), were isolated from the roots of Hippocratea celastroides K. Their structures were elucidated by spectroscopical and X-ray diffraction studies. Celastroidine A (1) (C50H74O5) was identified as a Diels-Alder adduct of a triterpene plus a diterpene and celastroidine B (2) as a beyerane, a type of dimer of two diterpene (C40H60O4). Both compounds could be formed in vivo by a Diels-Alder reaction. Celastroidine A showed some antifeeding activity against the stored grain insect Sitophyllus zeamays.Key words: Hippocratea celastroides, Hippocrataceae, roots, Diels-Alder adducts, diterpenoids, triterpenoids, x-ray diffraction, insect antifeedants, stored grain insects, Sitophyllus zeamays, insecticidal plants, Diels-Alderase.

High Yield Polyborosilazane Precursor for SiBN Ceramics

2014 ◽  
Vol 1004-1005 ◽  
pp. 409-414 ◽  
Author(s):  
Shuai Yong Jin ◽  
Kang Kang Guo ◽  
Hui Min Qi ◽  
Ya Ping Zhu ◽  
Fan Wang
Keyword(s):  
Photoelectron Spectroscopy ◽  
High Yield ◽  
Cross Linking ◽  
Differential Scanning Calorimetric ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
Ceramic Yield ◽  
X Ray ◽  
Amorphous Structures

The processible and high yield polyborosilazane (PBSZ) precursor for SiBN ceramics was prepared by coammonolysis reaction of dichlorosilane and trichloroborazine. The synthesized PBSZ precursor was characterized by Fourier Transform Infrared spectroscopy (FTIR),1H,11B, and29Si Nuclear Magnetic Resonance (NMR), and its ceramic conversion chemistry was investigated by differential scanning calorimetric (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and thermal gravimetric analysis (TGA). The PBSZ precursor is a viscous liquid and changes to an insoluble solid via a cross-linking reaction between the N-H group and Si-H group as post-heated from 60 to 180°C. The insoluble solid is transformed to Si3N4and BN amorphous structures with an approximately 95% ceramic yield after being pyrolyzed to 1000°C.

Facile One-Pot Synthesis and Crystal Structure of 2:1 Adducts of Myrcene (or Ocimene) with Benzoquinones

2020 ◽  
Vol 17 (8) ◽  
pp. 624-627
Author(s):  
Sujata V. Bhat ◽  
Rohan S. Pawar ◽  
P. Rajakannu
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Alder Reaction ◽  
Diels Alder ◽  
One Pot ◽  
Synthesis And Crystal Structure ◽  
X Ray ◽  
One Pot Synthesis ◽  
Diels Alder Reaction

One-pot tandem oxidation and double Diels-Alder reaction of myrcene or ocimene with in situ generated 1,4-benzoquinone or 1,2-benzoquinone at 0°C for 1.5 h yielded polyalkylated 1,4,4a,5,8,8a,9a,10a-octahydro-9,10-anthracenediones and bis(alkylated) 9,10-phenanthrenedione respectively. The structure of novel bis-adduct from ocimene, (1R,4aR,5S,8aS,9aS,10aR)-rel- 1,4,4a,5,8,8a,9a,10a-octahydro-2,6-dimethyl-1,5-bis(3-methyl-2-buten-1-yl)-9,10-anthracenedione, was elucidated through single crystal X-ray analysis.

X-Ray Diffraction Data for Lu(OH)3

1987 ◽  
Vol 2 (1) ◽  
pp. 39-40 ◽  
Author(s):  
D. F. Mullica ◽  
E. L. Sappenfield
Keyword(s):  
Powder Diffraction ◽  
Thermal Gravimetric Analysis ◽  
Diffraction Data ◽  
Cell Parameter ◽  
Gravimetric Analysis ◽  
Powder Diffraction Data ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
X Ray ◽  
Figures Of Merit

AbstractIndexed powder diffraction data for Lu(OH)3 are reported. The compound is cubic, Im3(No. 204), with a = 8.2221(3)Å, V = 555.84Å3, Z = 8, Dm = 5.36(4)Mg m−3 (Dx = 5.40Mg m−3). The refined cell parameter was determined by employing a Siemens Debye-Scherrer camera (Cu radiation, Ni filter). The indexed data were evaluated according to the quantitative figures of merit FN and M20 (F29 = 20(0.028,51) and M20 = 43.5). A thermal gravimetric analysis is presented. The JCPD S Diffraction File No. for Lu(OH)3 is 38–1500.

Structural Study of an Unusual Diels-Alder Adduct

1992 ◽  
Vol 45 (12) ◽  
pp. 2089 ◽  
Author(s):  
EL Ghisalberti ◽  
BW Skelton ◽  
AH White
Keyword(s):  
Single Crystal ◽  
Diffraction Study ◽  
Structural Study ◽  
Spectroscopic Studies ◽  
Diels Alder ◽  
X Ray Diffraction ◽  
X Ray ◽  
Naturally Occurring ◽  
Chemical Evidence ◽  
Alder Adduct

The structure of the compound obtained on heating the naturally occurring clerodane furanoditerpene (1) had been formulated as (2) on the basis of spectroscopic studies. A single-crystal X-ray diffraction study on the dihydro derivative of (2) has confirmed this and provides support for the stereochemistry previously assigned to (1) on the basis of chemical evidence.

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