C. Brouard et al., A CONVENIENT SYNTHESIS OF ,4-BIS(TRIMETHYLSILYLMETHYL)-5,6-DIHYDRO-2H-PYRANS THROUGH A CATALYZED HETERO-DIELS-ALDER REACTION, Synthetic communications, 24(21), 1994, pp. 3047-3053
In the presence of boron trifluoride etherate, 2,3-bis(trimethylsilylm
ethyl)-1,3-butadiene reacts with aldehydes and ketones to lead general
ly to an only product, resulting from an hetero Diels-Alder reaction.