Fused Multifunctionalized Chromenes from Tetraynes and α,β-Unsaturated Aldehydes.

摘要: We have developed a convenient and general method for synthesizing highly substituted cyclopenta[h]chromans via the reaction of tetrayne systems with α,β-unsaturated aldehyde. The formation C-C Caryl-O-Caryl bonds involves cascade HDDA reaction, an intermolecular aldehyde rearrangement. This approach requires no metals, catalysts, additives, or directing groups can be used wide range substrates. also exhibits excellent regioselectivity, producing all types fused chromans under mild conditions good to yields. It is anticipated that additional advances will allow direct reactions, enabling development more efficient rearrangement selective multiyne broader applicability. These comprise key strategy construction natural chroman core robust ubiquitous chromans.