Allylic substitution is arguably one of the most powerful tools for the creation of new C-C and C-heteroatom bonds in organic synthesis. The best example is the venerable Tsuji-Trost reaction, which is commonly employed as a region-and stereoselective method for the creation of C-C, C-O, C-N and C-S bonds. Despite the recognized utility and existing knowledge of this reaction, double allylic substitution sequences are surprisingly scarce, considering the high level of molecular complexity that could be attained through such one-pot approach. Indeed, the successive allylic alkylation of 3,4difunctionalized butene derivatives presents many challenges (Scheme 1A). First, the regioselective introduction of two nucleophiles implies discriminating between electrophilic positions 1 and 3 for the first substitution and positions 2 and 4 for the second one. In particular, only reaction at C 1 in the first step will induce migration of the olefin moiety and allow a productive process, while regioisomer B will not allow a second allylic substitution. In addition, the fact that compound A resulting from a first allylic substitution is also a substrate for a second allylic substitution raises chemoselectivity issues. If one wants to introduce two different nucleophiles, a competitive reaction leading to C could occur in a one-pot process. Finally, in order to be a useful tool for organic chemists, the reaction needs to depend on simple precursors and be carried out in a one-pot process. Most previous examples of double allylic substitution elude the question of chemoselectivity by employing a dual nucleophile. For example, in 2012 Clavier and co-workers reported the one-pot double allylation of 1,3-diketones using an allylic dicarbonate, an elegant example from readily available substrates (Scheme 1B). On the other hand, in order to introduce two different nucleophiles in each of the substitution, one has to tune the substrate in order to have two different leaving groups which can be substituted sequentially, as reported by Dieter et al. in 2008 (Scheme 1C). Although this latter example is chemoselective, the substrates are not readily available, require additional steps for the introduction of two different leaving groups and suffer from a lack of diversity. Herein, we propose to solve the question of regio-and chemoselective double allylic substitutions from readily available alkenyl vic-diols using a sequential dual catalysis approach, in which each catalytic system will allow the introduction of a different nucleophile at will. Taking inspiration from the work of Borhan's group on diol activation, we imagined that alkenyl vic-diols could be activated by trimethyl orthoacetate to form a cyclic orthoester intermediate (Scheme 1D). The addition of a Lewis acid would exacerbate the nucleophilicity of the orthoester intermediate, facilitating the first allylic substitution. During this process, ring-opening of the transient cyclic orthoester would result in the formation of an allylic acetate, which could sequentially undergo a classical Tsuji-Trost reaction in the presence of a palladium catalyst. This dual catalysis approach would solve the problems of chemoselectivity inherent to double allylic substitutions. Nevertheless, this raises the question of catalyst compatibility between the Lewis acid and Pd catalysts. The regioselectivity of each substitution will also be a key challenge for this double transformation.