The Simultaneous In-Situ Generation of Aldehydes and Phosphorus Ylides: A Convenient Multi-Step One-Pot Olefination Protocol

Abstract

The lithium α‐(dimethylamino)alkoxides resulting from the nucleophilic addition of an organolithium reagent to N,N‐dimethylformamide are basic enough to deprotonate alkyltriphenylphosphonium salts suspended in tetrahydrofuran. The aldehydes liberated by the spontaneous decomposition of the resulting α‐amino alcohols (hemiaminals) undergo a Wittig reaction with the simultaneously generated phosphorus ylides to afford olefins in excellent overall yields. This in situ method offers the unique advantage in its applicability to labile aldehydes which otherwise would become prey to (Z/E)‐isomerization or self‐condensation processes.

Novel Anti‐Markovnikov Regioselectivity in the Wacker Reaction of Styrenes

“…3,5‐Di‐ tert ‐butylstyrene (1 m) : The method of Schlosser and co‐workers26 was used. Potassium tert ‐butoxide (491 mg, 4.38 mmol) was dissolved in a solution of butyllithium in hexane (1.6 m , 2.8 mL, 4.48 mmol).…”

Strategies for the Selective Functionalization of Dichloropyridines at Various Sites

“…[17] Experimental Section General Remarks: Details concerning standard operations and the meaning of abbreviations can be found in previous publications from this laboratory. [18,19] 1 H and 13 C NMR spectra were recorded at 400 and 101 MHz, respectively. The solvent was CDCl 3 or, occasionally (marked with an asterisk), [D 6 ]DMSO.…”

Buttressing Effects Rerouting the Deprotonation and Functionalization of 1,3‐Dichloro‐ and 1,3‐Dibromobenzene

“…Working practices and abbreviations are specified in previous articles from this laboratory 19−21 . 1 H and 1 H‐decoupled 13 C NMR spectra were recorded of samples dissolved in deuteriochloroform at 400 and 101 MHz, respectively, relative to the internal standard tetramethylsilane (chemical shift δ = 0.00 ppm).…”