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There are several established approaches for the reductive fractionationof lignocellulose (e.g., “catalytic upstream biorefining" and “lignin-first" approaches) that lead to a lignin oil product that is composed primarily of dihydro-p-monolignols [e.g., 4-(3-hydroxypropyl)-2-methoxyphenol and 4-(3-hydroxypropyl)- 2,6-dimethoxyphenol]. Although effective catalytic methods have been developed to perform reductive or deoxygenativeprocesses on the lignin oil, the influence of the 3-hydroxypropylsubstituent on catalyst activity has previously beenoverlooked. Herein, to better understand the reactivity of thedepolymerized lignin oil obtained from catalytic upstream biorefiningprocesses, dihydro-p-coumaryl alcohol was selected asa model compound. Hydrogenation of this species in the presenceof Raney Ni with molecular hydrogen led to ring saturation(100% selectivity) in the absence of hydrodeoxygenation,whereas under hydrogen-transfer conditions with 2-propanol,hydrogenation occurred (&55% selectivity) simultaneouslywith hydrodeoxygenation (&40% selectivity). In a broadercontext, this study sheds light not only on the reactivity of dihydro-p-monolignols but also on the intricacies of the catalyticupstream biorefining reaction network in which these speciesare revealed to be key intermediates in the formation of less functionalized p-alkylphenols. [ABSTRACT FROM AUTHOR]