The potential of this method was further underpinned by the formal synthesis of active pharmaceutical ingredients (APIs) haloperidol, seratrodast and naturally occurring piperidine alkaloid (-)-sedamine. Haloperidol is extensively used in the treatment of schizophrenia and tourette's syndrome. The first synthesis of 18 F-labelled haloperidol was accomplished in a multistep process starting from N-phenylacetamide 114 and 4-chlorobutanoyl chloride 115 followed by nucleophilic displacement with commercially available piperidine nucleophile 116. Recently, the MacMillan group elegantly reported a photoredox enabled aldehyde C-H alkylation strategy for the synthesis of γ-chloroarylketone 120 via coupling of 4chlorobutanal 119 and 1-bromo-4-fluorobenzene 118. Nucleophilic displacement of ketone 120 with piperidine 116 delivered haloperidol 117. However, the practical usefulness of this approach is hampered by the use of very expensive 4-chlorobutanal. In contrast, by simply submitting commercially available and inexpensive 4-fluorobenzoyl chloride B2 and allyl chloride A4 to our reaction conditions followed by one-pot elimination and subsequent chemoselective double bond reduction afforded the desired ketone 120 in 61% yield over two steps, which can be converted to haloperidol 117 followed reported methods (Fig. ). Moreover, γchloroarylketone 120 can be employed to obtain dehydroxyhaloperidol, melperone and lenperone via nucleophilic displacement with commercially available corresponding piperidine derivatives. The synthesis of seratrodast, an antiasthmatic and eicosanoid antagonist was reported by Takai and coworkers. The key intermediate 122 is prepared via In-catalyzed reaction of diketone 121 with EtOH followed by NaBH4 reduction. In our approach, βchloroacylation of methyl-5-hexenoate A5 with benzoyl chloride B1 furnished compound 125. Base-mediated dehydrochlorination and subsequent reduction delivered the desired alcohol ester derivative 126, which can be transformed to seratrodast using the literature method (Fig. ). Next, we directed our focus to sedamine, a piperidne alkaloid, first isolated from sedum acre. Much effort has been devoted to synthesizing sedamine, either as a racemate or as a single enantiomer. The first synthesis of (-)-sedamine 132 was documented by the Beyerman group in 1956. Metal hydride mediated sequential reduction of aminoalcohol 129 and ketoacid 130 led to the formation of racemic sedamine 131, which could be converted to (-)-sedamine 132 following optical resolution with dibenzoyl-L-tartaric acid (Fig 7C). Of notable mention is the Ag-catalyzed asymmetric Mannich reaction developed by the Hoveyda et al. for the synthesis of (-)-sedamine using chiral ligand 136. Our method facilitates the generation of the piperidinone building block 139 of (-)-sedamine directly from amide A6 and benzoyl chloride B1 in two steps with 54% overall yield, allowing a greatly streamlined β-chloroacylation/cyclization sequence. (-)-sedamine 132 can be obtained from 139 following the reported methods as presented in Fig. . Importantly, this approach underscores the potential for the rapid library synthesis of different lactum analogues, as demonstrated in the formation of compound 109 (cf. Fig. ).