7743-31-9

Upstream product

• 79750-53-1 (E)-3-(4-nitrophenyl)prop-2-en-1-yl bromide 
• 603-35-0 triphenylphosphine 
• 2767-70-6 (p-nitrobenzyl)triphenylphosphonium bromide 
• 25798-60-1 (1-nitro-4-(prop-1-en-1-yl)benzene) 

Downstream Products

• 74026-42-9 2-<4-(4-Nitrophenyl)-1(Z),3(E)-butadienyl>-3-phenyloxiran 
• 74026-42-9 2-<4-(4-Nitrophenyl)-1(E),3(E)-butadienyl>-3-phenyloxiran 
• 136795-72-7 ttt-1-(p-methoxyphenyl)-6-(p-nitrophenyl)-1,3,5-hexatriene 
• 74026-46-3 cis-2,3-Dihydro-3-<2-(4-nitrophenyl)vinyl>-2-phenylfuran 
• 171732-81-3 2-[(1E,3E)-4-(4-Nitro-phenyl)-buta-1,3-dienyl]-benzaldehyde 
• 134272-10-9 (1S,8R,9S)-9-(4-Nitro-phenyl)-12-aza-tricyclo[6.3.2.0^2,7]trideca-2,4,6,10,12-pentaene-13-carboxylic acid methyl ester 
• 171867-02-0 Methyl α-azido-2-<(2E,4E)-4-(p-nitrophenyl)buta-1,3-dienyl>cinnamate 

Relevant academic research and scientific papers

6- and 8?-Ringschlussreaktionen von 2-Oxaheptatrienyl-Dipolen: Synthese von 3-Vinyl-2,3-dihydrofuranen und 2,3(6,7)-Dihydrooxepinen

The thermally induced ring expansion reactions of several butadienyloxiranes are described.The 3(E)-configurated epoxytrienes 11 are transformed predominantly into cis-3-vinyl-2,3-dihydrofurans 15, the trans-isomers 16 being formed as a minor component only with the derivatives a, c, and h.In contrast, thermolysis of the 3(Z)-butadienyloxiranes 12 leads always to a mixture of fivemembered ring products (15/16) and, additionally, dihyrooxepins (17 and 29, resp.).As mechanism of the ring expansion reactions a multistep sequence is proposed with 2-oxaheptatrienyl dipoles as intermediates, which undergo electrocyclisation with participation of either six or eight electrons leading to dihydrofurans and dihydrooxepins, resp.With relation to 1,7-cyclisation reactions of other extended dipole systems the importance of the stereochemistry in the starting materials is emphasised.