Transition metal-catalyzed reductive coupling reactions that avoid the need for pregeneration of air-and moisture-sensitive organometallic reagents provide an attractive route to highly functionalized synthetic intermediates. 1 Notably, reductive couplings of unsaturated compounds with aldehydes have demonstrated high efficiency for the construction of carboncarbon bonds in a number of contexts using alkynes, 2 1,3-dienes, or allenes (Scheme 1A). Couplings of alkenes with aldehydes, however, are more difficult, and methods are often restricted to intramolecular versions, highly activated alkenes such as norbornene and methylenecyclopropane, or hydroacylations of styrenes. Advances using triethylsilyl triflate as promoter enabled considerable improvements in olefin scope to include alkenes with aromatic aldehydes and tertiary aliphatic aldehydes (Scheme 1B). More recently, cobalt-and chromium co-catalyzed branch-selective coupling of alkenes with aldehydes through an alkyl chromium intermediate further broadened the scope of substrate combinations tolerated. Additionally, ironcatalyzed transfer hydrogenative coupling of alkenes with aromatic and aliphatic aldehydes and Brønsted acid enabled nickel-catalyzed hydroalkenylation of styrene derivatives with unactivated aldehydes provided further advances. Despite these developments, the majority of current methods for aldehyde-alkene reductive coupling are restricted to aromatic aldehydes, and the direct coupling reaction of abundantly available alkenes with unactivated aliphatic aldehydes still presents challenges in many cases.