ChemInform Abstract: Facile and Highly Selective Silylation of Vinylpyridines at the β-Olefinic Carbon by Magnesium-Promoted Reduction.

ChemInform ◽  
2016 ◽  
Vol 47 (33) ◽  
Author(s):  
Tianyuan Zhang ◽  
Zeyu Zhang ◽  
Yutaro Nishiyama ◽  
Hirofumi Maekawa
Keyword(s):  
Olefinic Carbon

scholarly journals The chemical behavior of terminally tert-butylated polyolefins

2015 ◽  
Vol 11 ◽  
pp. 1246-1258
Author(s):  
Dagmar Klein ◽  
Henning Hopf ◽  
Peter G Jones ◽  
Ina Dix ◽  
Ralf Hänel
Keyword(s):  
Catalytic Hydrogenation ◽  
Spectroscopic Data ◽  
Model Compound ◽  
Saturated Hydrocarbon ◽  
Complex Mixture ◽  
Diels Alder ◽  
Equivalent Amount ◽  
Chemical Behavior ◽  
Rearrangement Product ◽  
Olefinic Carbon

The chemical behavior of various oligoenes 2 has been studied. The catalytic hydrogenation of diene 3 yielded monoene 4. Triene 7 was hydrogenated to diene 8, monoene 9 and saturated hydrocarbon 10. Bromine addition to 3 and 7 yielded the dibromides 17 and 18, respectively, i.e., the oligoene system has been attacked at its terminal olefinic carbon atoms. Analogously, the higher vinylogs 19 and 20 yielded the 1,8- and 1,10-bromine adduts 23 and 24, respectively, when less than 1 equivalent of bromine was employed. Treatment of tetraene 19 with excess bromine provided tetrabromide 25. In epoxidation reactions, both with meta-chloroperbenzoic acid (MCPBA) and dimethyldioxirane (DMDO) two model oligoenes were studied: triene 7 and tetraene 19. Whereas 7 furnished the rearrangement product 31 with MCPBA, it yielded the symmetrical epoxide 32 with DMDO. Analogously, 19 was converted to mono-epoxide 33 with MCPBA and to 34 with DMDO. Diels–Alder addition of 7 with N-phenyltriazolinedione (PTAD) did not take place. Extension of the conjugated π-system to the next higher vinylog, 19, caused NPTD-addition to the symmetrical adduct 37 in good yield. Comparable results were observed on adding NPTD (equivalent amount) to pentaene 20 and hexaene 21. Using 36 in excess provided the 2:1-adduct 40 from 21 and led to a complex mixture of adducts from heptaene 22. With tetracyanoethylene (TCNE) as the dienophile, tetraolefin 19 yielded the symmetrical adduct 43, although the reaction temperature had to be increased. Pentaene 20 and hexaene 21 led to corresponding results, adducts 44 and 45 being produced in acceptable yields. With nonaene 42 and TCNE the 2:1-adduct 48 was generated according to its spectroscopic data. Exploratory photochemical studies were carried out with tetraene 19 as the model compound. On irradiation this reacted with oxygen to the stable endo-peroxide 52.

On the sterochemistry of exchange at olefinic carbon

1968 ◽  
Vol 15 (2) ◽  
pp. 279-285 ◽  
Author(s):  
A.N. Nesmeyanov ◽  
A.E. Borisov ◽  
N.V. Novikova ◽  
E.I. Fedin
Keyword(s):  
Olefinic Carbon

O-N, S-N and N-N exchange reactions at olefinic carbon atoms: Facile synthetic method for β-trifluoroacetylvinylamines

1989 ◽  
Vol 30 (45) ◽  
pp. 6173-6176 ◽  
Author(s):  
Masaru Hojo ◽  
Ryōichi Masuda ◽  
Etsuji Okada ◽  
Syūhei Sakaguchi ◽  
Hitoshi Narumiya ◽  
...  
Keyword(s):  
Synthetic Method ◽  
Exchange Reactions ◽  
Olefinic Carbon

THEORETICAL MECHANISTIC STUDY ON THE RADICAL-NEUTRAL REACTION OF CH(X2Π) WITH CH2CO

2010 ◽  
Vol 09 (02) ◽  
pp. 423-433 ◽  
Author(s):  
SHA LI ◽  
YANG GAO ◽  
XIU-JUAN JIA ◽  
HAO SUN ◽  
RONG-SHUN WANG ◽  
...  
Keyword(s):  
Potential Energy ◽  
Energy Surface ◽  
Single Point ◽  
Stationary Points ◽  
Mechanistic Study ◽  
Intrinsic Reaction Coordinate ◽  
Title Reaction ◽  
Olefinic Carbon ◽  
Energy Information ◽  
Good Agreement

A theoretical survey on the potential energy surface for the CH (X2Π) + CH2CO reaction has been carried out. The geometries and energies of all stationary points involved in the reaction are calculated at the UB3LYP/6-311+G(d, p) level. And the more accurate energy information is provided by single point calculations at the UCCSD(T)/6-311++G(2d, 2p) level. Relationships of the reactants, transition states, intermediates, and products are confirmed by the intrinsic reaction coordinate (IRC) calculations. Our calculations demonstrate that this reaction is most likely initiated by carbon-to-olefinic carbon attack manners. The results suggest that P1 (C2H3 + CO) is the most important product through two competitive channels R → IM1 → TS1/P1 → P1 (C2H3 + CO) and R → IM1 → TS1/6 → IM6 → TS6/P1 → P1 (C2H3 + CO) . This study presents highlights of the mechanism of the title reaction, which is in good agreement with experimental results.

Sign in / Sign up

Export Citation Format

Share Document