Abstract
ß-Nitrostyrenes l react with triethylaluminium or diethylaluminium chloride in diethyl ether solution and under nitrogen or argon to generate the alkenes 2 and the hydroximoyl chlorides 3 after work-up with ice-cold, cone, hydrochloric acid. The formation of the alkenes 2 is proposed to be a free-radical reaction via NO2/alkyl substitution since the yields of the alkenes 2 are increased in the presence of benzoyl peroxide (Bz2O2) and decreased in the presence of galvinoxyl. Only the alkenes 2 are produced with a high stereoselectivity for the E isomers when ß-nitrostyrenes react with triethylaluminium in the presence of one to two equivalents of Bz2O2 as free-radical initiator.. The mechanism of the generation of the hydroximoyl chlorides 3 is proposed to proceed through a 1,4-addition pathway to produce nitronates A, then the protonated nitronates B or the nitroso cations C are trapped by chloride ion to form the final products. The yields of compounds 3 are also improved by the presence of Lewis acids such as MgCl2. Medium to high yields of the hydroximoyl chlorides 3 and traces or low yields of the alkenes 2 are generated when triethylaluminium or diethylaluminium chloride react with ß-nitrostyrenes in the presence of three equivalents of MgCl2 under argon.
| Original language | English |
|---|---|
| Pages (from-to) | 47-52 |
| Number of pages | 6 |
| Journal | Journal of the Chemical Society - Perkin Transactions 1 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - 1999 Jan 1 |
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Free radical reactions to generate alkenes and/or ionic reactions to generate hydroximoyl chlorides when ß-nitrostyrenes react with triethylaluminium or diethylaluminium chloride. / Chu, Cheng Ming; Liu, Ju Tsung; Lin, Wen-Wei; Yao, Ching-Fa.
In: Journal of the Chemical Society - Perkin Transactions 1, No. 1, 01.01.1999, p. 47-52.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Free radical reactions to generate alkenes and/or ionic reactions to generate hydroximoyl chlorides when ß-nitrostyrenes react with triethylaluminium or diethylaluminium chloride
AU - Chu, Cheng Ming
AU - Liu, Ju Tsung
AU - Lin, Wen-Wei
AU - Yao, Ching-Fa
PY - 1999/1/1
Y1 - 1999/1/1
N2 - ß-Nitrostyrenes l react with triethylaluminium or diethylaluminium chloride in diethyl ether solution and under nitrogen or argon to generate the alkenes 2 and the hydroximoyl chlorides 3 after work-up with ice-cold, cone, hydrochloric acid. The formation of the alkenes 2 is proposed to be a free-radical reaction via NO2/alkyl substitution since the yields of the alkenes 2 are increased in the presence of benzoyl peroxide (Bz2O2) and decreased in the presence of galvinoxyl. Only the alkenes 2 are produced with a high stereoselectivity for the E isomers when ß-nitrostyrenes react with triethylaluminium in the presence of one to two equivalents of Bz2O2 as free-radical initiator.. The mechanism of the generation of the hydroximoyl chlorides 3 is proposed to proceed through a 1,4-addition pathway to produce nitronates A, then the protonated nitronates B or the nitroso cations C are trapped by chloride ion to form the final products. The yields of compounds 3 are also improved by the presence of Lewis acids such as MgCl2. Medium to high yields of the hydroximoyl chlorides 3 and traces or low yields of the alkenes 2 are generated when triethylaluminium or diethylaluminium chloride react with ß-nitrostyrenes in the presence of three equivalents of MgCl2 under argon.
AB - ß-Nitrostyrenes l react with triethylaluminium or diethylaluminium chloride in diethyl ether solution and under nitrogen or argon to generate the alkenes 2 and the hydroximoyl chlorides 3 after work-up with ice-cold, cone, hydrochloric acid. The formation of the alkenes 2 is proposed to be a free-radical reaction via NO2/alkyl substitution since the yields of the alkenes 2 are increased in the presence of benzoyl peroxide (Bz2O2) and decreased in the presence of galvinoxyl. Only the alkenes 2 are produced with a high stereoselectivity for the E isomers when ß-nitrostyrenes react with triethylaluminium in the presence of one to two equivalents of Bz2O2 as free-radical initiator.. The mechanism of the generation of the hydroximoyl chlorides 3 is proposed to proceed through a 1,4-addition pathway to produce nitronates A, then the protonated nitronates B or the nitroso cations C are trapped by chloride ion to form the final products. The yields of compounds 3 are also improved by the presence of Lewis acids such as MgCl2. Medium to high yields of the hydroximoyl chlorides 3 and traces or low yields of the alkenes 2 are generated when triethylaluminium or diethylaluminium chloride react with ß-nitrostyrenes in the presence of three equivalents of MgCl2 under argon.
UR - http://www.scopus.com/inward/record.url?scp=2442691014&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=2442691014&partnerID=8YFLogxK
U2 - 10.1039/a807156j
DO - 10.1039/a807156j
M3 - Article
AN - SCOPUS:2442691014
SP - 47
EP - 52
JO - Journal of the Chemical Society, Perkin Transactions 1
JF - Journal of the Chemical Society, Perkin Transactions 1
SN - 1470-4358
IS - 1
ER -