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Among many synthetically useful palladium-catalyzed transformations, 1 a reaction of uncommon pattern is the palladiumcatalyzed nucleophilic addition of organic halides to ketones and aldehydes, although such addition shown in eq 1 is the most frequently encountered reaction in traditional main-group metal chemistry. Nowadays, however, the reaction of this type is being opened in palladium chemistry; vinylpalladium halides, generated from aryl halides, alkynes, and catalytic amounts of palladium, underwent intramolecular nucleophilic addition to aryl ketones, 2a aldehydes, 2b and nitriles. 3 We now wish to report that the intramolecular nucleophilic addition of aryl bromides 1 to ketones proceeds very smoothly in the presence of palladium catalyst to give the corresponding cyclic alcohols 2 in good to high yields (eq 2). This is a Grignard-type reaction using a palladium catalyst. 4

The hydroxy group regulates the stereoselectivity in a modification of the titanium‐mediated Kulinkovich cyclopropanation procedure (see scheme). This method provides a diastereoselective synthesis of trans‐1,2‐dialkylcyclopropanols, which starts with homoallylic alcohols and proceeds via a bicyclic titanacyclopropane intermediate. Enantiopure products may also be obtained if the corresponding chiral alcohols are used.

A new approach to isoprostanes and neuroprostanes featuring cis-dialkyl stereochemistry at the cyclopentane ring has been developed by employing an intramolecular cross-coupling reaction of an alkyl iodide and a tethered alkenylsiloxane for stereoselective installation of a functionalized omega-side chain.