673-32-5Relevant articles and documents
Crossed beam reaction of phenyl radicals with unsaturated hydrocarbon molecules. I. Chemical dynamics of phenylmethylacetylene (C6H5CCCH3;X1A') formation from reaction of C6H5(X2A1) with methylacetylene, CH3CCH(X1A1)
Kaiser,Asvany,Lee,Bettinger,Schleyer,Schaefer III
, p. 4994 - 5001 (2000)
The chemical reaction dynamics to form phenylmethylacetylene, C6H5CCCH3(X2A'), via reactive collisions of the phenyl radical C6H5(X2A1) with methylacetylene, CH3CCH(X1A1), are unraveled under single collision conditions in a crossed molecular beam experiment at a collision energy of 140 kJ mol-1. The laboratory angular distribution and time-of-flight spectra of C9H8+ at m/e = 116 indicate the existence of a phenyl radical versus hydrogen replacement pathway. Partially deuterated methylacetylene, CH3CCD(X1A1), was used to identify the site of the carbon-hydrogen bond cleavage. Only the loss of the acetylenic hydrogen atom was observed; the methyl group is conserved in the reaction. Electronic structure calculations reveal that the reaction has an entrance barrier of about 17 KJ mol-1. Forward-convolution fitting of our data shows that the chemical reaction dynamics are on the boundary between an osculating complex and a direct reaction and are governed by an initial attack of the C6H5 radical to the π electron density of the Cl carbon atom of the methylacetylene molecule to form a short lived, highly rovibrationally excited (C6H5)HCCCH3 intermediate. The latter loses a hydrogen atom to form the phenylmethylacetylene molecule on the 2A' surface. The phenylallene isomer channel was not observed experimentally. The dynamics of the title reaction and the identification of the phenyl versus hydrogen exchange have a profound impact on combustion chemistry and chemical processes in outflows of carbon stars. For the first time, the reaction of phenyl radicals with acetylene and/or substituted acetylene is inferred experimentally as a feasible, possibly elementary reaction in the stepwise growth of polycyclic aromatic hydrocarbon precursor molecules and alkyl substituted species in high temperature environments such as photospheres of carbon stars and oxygen poor combustion systems.
Dewar,Fahey
, p. 3645,3647,3648 (1963)
Fritsch-Buttenberg-Wiechell rearrangement of magnesium alkylidene carbenoids leading to the formation of alkynes
Ando, Akane,Imafuji, Aki,Kimura, Tsutomu,Sekiguchi, Koto
, p. 1352 - 1359 (2021/06/06)
A series of 1-heteroatom-substituted vinyl p-tolyl sulfoxides were prepared and treated with organometallic reagents to evaluate which combination of sulfoxides and organometallic reagents yielded alkynes the most efficiently. The use of 1-chlorovinyl p-tolyl sulfoxide and isopropylmagnesium chloride was optimal for this purpose. A variety of 1-chlorovinyl p-tolyl sulfoxides were prepared from carbonyl compounds and chloromethyl p-tolyl sulfoxide and were converted into alkynes via the sulfoxide/magnesium exchange reaction and subsequent Fritsch-Buttenberg-Wiechell (FBW) rearrangement of the resulting magnesium alkylidene carbenoids. The mechanism of the FBW rearrangement of magnesium alkylidene carbenoids was studied by using13C-labeled sulfoxides and by using DFT calculations.
Rh(iii)-Catalyzed olefination to build diverse oxazole derivatives from functional alkynes
He, Yuan,Zheng, Ting,Huang, Yin-Hui,Dong, Lin
supporting information, p. 4937 - 4942 (2021/06/16)
A novel Rh(iii)-catalyzed olefination reaction of oxazoles to generate diverse oxazole skeleton derivatives has been realized by directly using oxazole as the directing group. The reaction could tolerate many functional groups, affording complex oxazole derivatives with long chain alkenyls in moderate to good yields, which might find applications in the construction of diverse compounds.
Regio- And stereoselective electrochemical synthesis of sulfonylated enethers from alkynes and sulfonyl hydrazides
Du, Wu-Bo,Wang, Ning-Ning,Pan, Chao,Ni, Shao-Fei,Wen, Li-Rong,Li, Ming,Zhang, Lin-Bao
supporting information, p. 2420 - 2426 (2021/04/07)
An electrooxidative direct difunctionalization of internal alkynes with sulfonyl hydrazides has been developed for the construction of sulfonated enethers. In this transformation, metal catalysts or stoichiometric amount of oxidants are not required and molecular nitrogen and hydrogen are the sole byproducts, providing a simple and green approach for preparing various sulfonyl tetrasubstituted alkenes. Notably, the protocol could be efficiently scaled up and the follow-up procedures of the corresponding functionalized alkenes demonstrate the practicality of the electrochemical synthesis.
