1208258-49-4Relevant academic research and scientific papers
Unusual [3+1] cycloaddition of a stable silylene with a 2,3-diazabuta-l,3-diene versus [4+1] cycloaddition toward a buta-l,3-diene
Xiong, Yun,Yao, Shenglai,Driess, Matthias
experimental part, p. 987 - 990 (2010/04/25)
Cycloaddition reactions of the thermally stable N-heterocyclic silylene LSi: 1 {L = CH[(C=CH2)CMe][N(Ar)J2], Ar = 2,6-{Pr 2C6H3} with acetone azine (l, l, 4, 4-tetramethyl-2,3-diazabuta-l,3-diene) and buta-l,3-diene derivatives have been probed. Unexpectedly, acetone azine undergoes a unique [3+1] cycloaddition to give the 1-sila-2,3-diazacyclobutane 2 and its 1-sila-2,3-diazacyclobutane isomer 3. The latter rearranges further to decrease ring strain, affording the corresponding 1-sila-4, 5-diazacyclohex-3-ene 4. In contrast, reaction of 1 with isoelectronic 2,3-dimethylbuta-l,3-diene furnishes the expected [4+1] cycloaddition product silacyclopentane 5. The new compounds 2-5 were spectroscopically characterized, including single-crystal X-ray analyses of 2,4, and 5.
