A highly stereoselective protocol is reported for customizing functionalized carbocyclic building blocks (β‐hydroxy esters) and bicyclic lactones with a stereoarray that contains contiguous tertiary carbinol and all‐carbon stereocenters. The efficient asymmetric induction and diastereofacial selective addition of allyl and propargyl indiums to hindered α,α‐disubstituted cycloalkanones is presented. The stereochemistry of representative products was unequivocally established from single‐crystal X‐ray crystal structure analyses, and a plausible reaction pathway was proposed to support the high diastereofacial selectivity.

In this Article, we report our successful attempt on the Pd(II)-catalyzed, bidentate directing group-aided, chemoselective acetoxylation/substitution of remote ε-C(sp)-H bonds using heteroaryl-aryl-based biaryl systems. While the bidentate directing group (BDG)-aided, C-H activation, and functionalization/acetoxylation of the β-, γ-, and δ-C-H bonds of the appropriate carboxamide systems were well documented, there exist only rare reports dealing with the C-H activation and functionalization of remote ε-C-H bonds of appropriate substrates. Especially, the BDG-aided chemoselective acetoxylation of the remote ε-C(sp)-H bond over cyclization has not been explored well. Accordingly, in this work, the treatment of various picolinamides/oxalylamides/pyrazine-2-carboxamides 4/7/9/11, which were derived from the corresponding C-3 arylated furfurylamines or thiophen-2-ylmethanamines with PhI(OAc) in the presence of the Pd(OAc) catalyst, successfully afforded the corresponding ε-C-H acetoxylated products. The chemoselective acetoxylation of the ε-C-H bond was possible and facilitated by the biaryl substrate 4/7/9/11 and not by the biaryl substrate 2a.

The palladium(II)‐promoted, bidentate ligand‐assisted regioselective C−H activation/arylation of the C‐3 position of 2‐ or 3‐(aminoalkyl)‐thiophene and furfurylamine derivatives with various aryl‐/heteroaryl iodides was reported. Various aryl‐/heteroaryl iodides and bidentate ligands, such as, picolinamide, quinoline‐2‐carboxamide, pyrazine‐2‐carboxamide and oxalylamide were examined for accomplishing the regioselective palladium(II)‐promoted C−H arylation and C−C bond formation at the C‐3 position of the 2‐/3‐(aminoalkyl)‐thiophene and furfurylamine derivatives. The X‐ray structures of the regioisomers 8 c and 9 c confirmed the observed regiselectivity. This C−H activation/arylation method gave an access to several C3‐arylated 2/3‐(aminoalkyl)‐thiophene‐ and furfurylamine based biaryl scaffolds that are analogous to biologically active C3‐arylated 2/3‐(aminoalkyl)‐thiophenes and furfurylamines.

A highly diastereoselective synthesis of the title amino acid derivatives (III), (XII), (XX), and (XXIII) is presented.

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