Catalytic enantioselective conjunctive cross-couplings that employ Grignard reagents are shown to furnish an array of non-racemic chiral organoboronic esters in an efficient and highly selective fashion. The utility of sodium triflate in facilitating this reaction is two-fold: it enables "ate" complex formation and overcomes catalytic inhibition by halide ions.

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Aryl alkynoate esters undergo gold-catalyzed spirocyclization under mild conditions, affording spirolactones in high yields. This approach obviates the need for stoichiometric halogenating reagents typically employed for alkyne activation in related transformations. Water was found to play a critical role in governing the product selectivity. Anhydrous conditions lead selectively to coumarin products, as has previously been observed for aryl alkynoate esters, while the addition of 1 equiv of water leads selectively to spirocycle formation.

Organoboron ‘ate’ complexes undergo a net vinyl insertion reaction to give 1,1-disubstituted alkenyl boronic esters when treated with stoichiometric allyl acetate and a palladium catalyst. Reactions that employ vinyllithium afforded good to excellent yields after one hour, while reactions that employ vinylmagnesium chloride furnished modest to good yields after 18 hours.

Enantioselective conjunctive cross-coupling with propargylic carbonates affords β-boryl allenes as the reaction product. The reaction is found to proceed through the intermediacy of dimethoxyboronate complexes that are generated in situ by a strain-induced ligand exchange reaction.

Organoboron “ate” complexes undergo a net vinyl insertion reaction to give 1,1‐disubstituted alkenyl boronic esters when treated with stoichiometric allyl acetate and a palladium catalyst. Reactions that employ vinyllithium afforded good to excellent yields after one hour, while reactions that employ vinylmagnesium chloride furnished modest to good yields after 18 hours.

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Facile One-Pot Synthesis of Tetrahydroisoquinolines from Amino Acids via Hypochlorite-Mediated Decarboxylation and Pictet-Spengler Condensation. -Oxidative decarboxylation of -amino acids provides the corresponding aldehydes which are converted into tetrahydroquinolines by addition of dopamine via Pictet--Spengler reaction. The two-step sequence is performed in a one-pot manner. -(MARESH*, J. J.; CROWE, S. O.; RALKO, A. A.; APARECE, M. D.; MURPHY, C. M.; KRZESZOWIEC, M.; MULLOWNEY, M. W.; Tetrahedron Lett. 55 (2014) 36, 5047-5051, http://dx.