Chemistry of acylals, part IV: BF3-catalyzed formation of substituted α,α′-bis(arylmethylidene)cycloalkanones from acylals and 1-cycloalkenyl trimethylsilyl ethers

Article abstract of DOI:10.1055/s-2007-990881

When mixtures of an aromatic aldehyde acylal and a I-cycloalkenyl trimethylsilyl ether in dichloromethane were treated with boron trifluoride at room temperature, the corresponding α,α′-bis(arylmethylidene) cycloalkanones were formed. The yield was sensitive to both the acetal/ether ratio and the structure of the acylal. The best results, up to 97% yield, were obtained when acylals containing a diacetoxy moiety were reacted with 1-cyclohexenyl trimethylsilyl ether with an acetal-to-ether ratio of 2:1. Georg Thieme Verlag Stuttgart.