DR ANTHONY MELVIN CRASTO,WorldDrugTracker, helping millions, A 90 % paralysed man in action for you, I am suffering from transverse mylitis and bound to a wheel chair, With death on the horizon, nothing will not stop me except God
DR ANTHONY MELVIN CRASTO Ph.D ( ICT, Mumbai) , INDIA 30 Yrs Exp. in the feld of Organic Chemistry. Serving chemists around the world. Helping them with websites on Chemistry.Millions of hits on google, world acclamation from industry, academia, drug authorities for websites, blogs and educational contribution
n

Sunday, 6 April 2014

Ethyl acetoacetate 乙酰乙酸乙酯 teaches you Organic spectroscopy... brush up?????

read at
http://orgspectroscopyint.blogspot.in/2014/04/ethyl-acetoacetate-teaches-you-organic.html
Ethyl acetoacetate
Ethyl 3-oxobutanoate
Acetoacetic acid ethyl ester
Ethyl acetylacetate
3-Oxobutanoic acid ethyl ester



Ethyl acetoacetate is produced industrially by treatment of diketene with ethanol.
The preparation of ethyl acetoacetate is a classic laboratory procedure.[2] It is prepared via the Claisen condensation of ethyl acetate. Two moles of ethyl acetate condense to form one mole each of ethyl acetoacetate and ethanol.

Preparation of ethyl acetoacetate.









Structure: structure

IUPAC Name: ethyl 3-oxobutanoate (ethyl acetoacetate)

Analysis: C6H10O3: MW = 130.14


The molecule contains an oxygen, and from the analysis, contains two double bonds, carbonyls or rings.
The mass spectrum displays a molecular ion and the base peak represents the formation of the acylium ion, indicating the presence of a methyl adjacent to a carbonyl. The presence of an m-45 peak strongly suggests the presence of an ethoxy group.
The 13C spectrum contains six peaks, indicating that all carbons are unique. The quartets at  14 and 24 represent relatively simple methyl groups; the triplets at  59 and 47 represent a CH2 groups bonded to mildly electronegative groups; the singlets at  207 and 172 are in the carbonyl region, and most likely a ketone or aldehyde ( 207) and an ester ( 172).
The proton NMR shows evidence for an ethyl group and isolated CH2 and CH3 groups. The methylene of the ethyl group must be next to an electronegative atom (most likely oxygen) suggesting an -OCH2CH3 group. The isolated CH2 must also be flanked by mildly electronegative groups, and the isolated CH3 is in the region often observed for methyls adjacent to carbonyls.
The IR is consistent with a simple saturated hydrocarbon, possibly containing two carbonyls (based on the side peak at  1670 cm-1). The minor peak at 3400 cm-1 is too small to be an -OH.
The simplest structure which is consistent with all of these data would be a dicarbonyl compound containing an ethoxy residue and a methyl ketone (based on the presence of the acylium ion in the MS).
http://orgspectroscopyint.blogspot.in/2014/04/ethyl-acetoacetate-teaches-you-organic.html

......................

1H NMR
NMR Spectrum
The proton NMR has a quartet coupled to a triplet, indicative of an ethyl group. The CH2 must be adjacent to an electron withdrawing group since it is shifted to  4.1. The two singlets at  2.2 and 3.2 suggest isolated CH2 and CH3 groups and the CH2 must be adjacent to one or more electronegative groups.

http://orgspectroscopyint.blogspot.in/2014/04/ethyl-acetoacetate-teaches-you-organic.html



http://orgspectroscopyint.blogspot.in/2014/04/ethyl-acetoacetate-teaches-you-organic.html
................................................................
13C NMR
13C NMR Assignments: C-13 assignments
13C NMR Data: q-13.6; q-24.2; t-59.2; t-46.6; s-172.0; s-207.1 
The 13C spectrum contains six peaks, indicating that all carbons are unique. The quartets at  14 and 24 represent relatively simple methyl groups; the triplets at  59 and 47 represent a CH2 groups bonded to mildly electronegative groups; the singlets at  207 and 172 are in the carbonyl region, and most likely a ketone or aldehyde ( 207) and an ester ( 172).




spectrum for Ethyl acetoacetate






ethyl acetoacetate CH3COCH2COOCH2CH3

................................

MASS SPECTROSCOPY
Mass Spectrum



Mass Spectrum Fragments: C-13 assignments
The mass spectrum consists of a molecular ion at 130, an m-15 peak at 115, which is consistent with loss of a CH3 group, an m-43 peak (loss of acylium), an m-45 peak (loss of CH3CH2O-), and a base peak at m-43(m/e = 43) which suggests the formation of an acylium ion (CH3-CO). The spectrum is consistent with a molecule which can lose methyl or ethoxy radicals, or can undergo fragmentation to form the acylium radical cation.


...............................

IR

3400-3200 cm-1: no OH peak (too small) 3100 cm-1: no significant peak, suggesting no unsaturated CH 2900 cm-1: strong peak suggesting saturated CH 2200 cm-1: no unsymmetrical triple bonds 1710 cm-1: strong carbonyl with a second peak at 1670 cm-1, suggesting a the possibility of two carbonyls 1600 cm-1: no significant peaks, suggesting no carbon-carbon double bonds




http://orgspectroscopyint.blogspot.in/2014/04/ethyl-acetoacetate-teaches-you-organic.html




2D [1H,1H]-TOCSY


spectrum for Ethyl acetoacetate

spectrum for Ethyl acetoacetate1D DEPT135





spectrum for Ethyl acetoacetate2D [1H,13C]-HSQC



spectrum for Ethyl acetoacetate2D [1H,13C]-HMBC





spectrum for Ethyl acetoacetate2D [1H,1H]-COSY


spectrum for Ethyl acetoacetate2D [1H,13C]-HMQC

http://orgspectroscopyint.blogspot.in/2014/04/ethyl-acetoacetate-teaches-you-organic.html

Tuesday, 25 March 2014

A solution to fluoronium riddle

fluoronium
The presence of a symmetrical fluoronium ion is confirmed by the 1:1 mixture of reaction products

The first evidence for hypervalent fluorine cations, or fluoronium ions, in solution has been found by US chemists. The research lays the foundations for characterising fluoronium ions – where the fluorine has two bonds and a formal positive charge – directly by spectroscopy and improving our understanding of fluorine’s interactions in organic chemistry
 

Sunday, 16 March 2014

An efficient Cu(II)-bis(oxazoline)-based polymer immobilised ionic liquid phase catalyst for asymmetric carbon-carbon bond formation

An efficient Cu(II)-bis(oxazoline)-based polymer immobilised ionic liquid phase catalyst for asymmetric carbon-carbon bond formation

Green Chem., 2014, 16,1470-1479
DOI: 10.1039/C3GC41378K, Paper
Simon Doherty, Julian G. Knight, Jack R. Ellison, Peter Goodrich, Leanne Hall, Christopher Hardacre, Mark J. Muldoon, Soomin Park, Ana Ribeiro, Carlos Alberto Nieto de Castro, Maria Jose Lourenco, Paul Davey
Asymmetric carbon-carbon bond forming reactions were catalysed by heterogeneous copper(II)-bis(oxazoline)-based PIILP systems.


The asymmetric Diels–Alder reaction between N-acryloyloxazolidinone and cyclopentadiene and the Mukaiyama-aldol reaction between methylpyruvate and 1-phenyl-1-trimethylsilyloxyethene have been catalysed by heterogeneous copper(II)-bis(oxazoline)-based polymer immobilised ionic liquid phase (PIILP) systems generated from a range of linear and cross linked ionic polymers. In both reactions selectivity and ee were strongly influenced by the choice of polymer. A comparison of the performance of a range of Cu(II)-bis(oxazoline)-PIILP catalyst systems against analogous supported ionic liquid phase (SILP) heterogeneous catalysts as well as their homogeneous counterparts has been undertaken and their relative merits evaluated.

Saturday, 15 March 2014

Free Download Analysis and Purification Methods in Combinatorial Chemistry

Free Download Analysis and Purification Methods in Combinatorial Chemistry edited by Bing Yan


http://chemistry.com.pk/books/analysis-and-purification-methods-in-combinatorial-chemistry/
Follow us

Muhammad Hasnain

Founder at Chemistry.Com.Pk
is the founder and author at Chemistry.Com.Pk. He did M.Sc in organic chemistry. Currently he is doing M.Phil leading to Ph.D in chemistry from Department of chemistry, Federal Urdu University of Arts, Sciences and Technology, Karachi. He loves to write about chemistry.

CHEMDRAW PRO 8.0

CHEMDRAW PRO 8.0

ChemDraw-logoChemDraw is a leading chemistry molecules drawing software. ChemDraw is easy to use and best software for drawing a molecule structures and finding stereochemistry of the molecules.
Features
  • easy to use
  • stereochemistry
  • atom numbers
  • templates each and every type of bond arrows
  • mass fragmentations
and much more….
Screenshot
ChemDraw Pro 8.0
ChemDraw Pro 8.0 provides chemists with a rich set of easy to use tools for creating publication ready, scientifically meaningful drawings of molecules and reactions.
Free download ChemDraw Pro 8.0 full version with product key and serial number from following download link. This download link is test personally and found viruses and spam free.
download button
click link
Specifications
Operating System: Windows 95/NT/98/2000/XP, Windows 7
Size: 47 MB

Tuesday, 11 March 2014

One-step synthesis of pyridines and dihydropyridines in a continuous flow microwave reactor


Figure 1: Microwave flow reactor for the Bohlmann–Rahtz synthesis of pyridine 2b.

 read at
http://www.beilstein-journals.org/bjoc/single/articleFullText.htm?publicId=1860-5397-9-232 

The Bohlmann–Rahtz pyridine synthesis and the Hantzsch dihydropyridine synthesis can be carried out in a microwave flow reactor or using a conductive heating flow platform for the continuous processing of material. 
In the Bohlmann–Rahtz reaction, the use of a Brønsted acid catalyst allows Michael addition and cyclodehydration to be carried out in a single step without isolation of intermediates to give the corresponding trisubstituted pyridine as a single regioisomer in good yield. 
Furthermore, 3-substituted propargyl aldehydes undergo Hantzsch dihydropyridine synthesis in preference to Bohlmann–Rahtz reaction in a very high yielding process that is readily transferred to continuous flow processing.


Mark C. Bagley1Email of corresponding author, Vincenzo Fusillo2, Robert L. Jenkins2, M. Caterina Lubinu2 andChristopher Mason3
1Department of Chemistry, School of Life Sciences, University of Sussex, Falmer, Brighton, East Sussex, BN1 9QJ, UK
2School of Chemistry, Main Building, Cardiff University, Park Place, Cardiff, CF10 3AT, UK
3CEM Microwave Technology Ltd, 2 Middle Slade, Buckingham, MK18 1WA, UK

This article is part of the Thematic Series "Chemistry in flow systems III".
Guest Editor: A. Kirschning
Beilstein J. Org. Chem. 2013, 9, 1957–1968.