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The Hoppe reaction, which is an allylation reaction of aldehydes using an optically active titanated crotyl carbamate intermediate generated from the corresponding N,N-diisopropyl crotyl carbamate with n-BuLi/(-)-sparteine, was in most cases applied to achiral aldehydes. In this work an extension of this reaction is reported using a racemic γ-alkoxy allyltitanate ( 17) and an optically active aldehyde ( 16) to deliver in good yield the anti adduct 18 as the major isomer. When the corresponding δ-lactol 24 was used in place of aldehyde 16, the anti adduct 25 was obtained in 94% yield as the only product. Structural modifications effected on 25 delivered aldehyde 28 which was in turn submitted to a second allylation reaction in the presence of the optically active titanated crotyl carbamate 2, prepared as described by Hoppe from crotyl carbamate 1, to conduct to compound 29 in 80% yield. This derivative corresponds to a potential precursor of the C1-C9 portion of Tylonolide, aglycon of Tylosin (4).Allylation of aldehydes have been largely described in the literature for many years. 1 In most cases the diastereoselectivities obtained were fair to excellent, in an S E ′ Lewis-acid-catalyzed reaction 2,3 via an open transition state or via a Zimmerman-Traxler transition state in others cases. 4 The enantioselectivity in these reactions arise either from the allylmetal or the aldehyde, or from both enantiopure partners.