Reactions of Sodium Diisopropylamide: Liquid-Phase and Solid–Liquid Phase-Transfer Catalysis by N,N,N′,N″,N″-Pentamethyldiethylenetriamine

Abstract

Sodium diisopropylamide (NaDA) in N,N-dimethylethylamine (DMEA) and DMEA−hydrocarbon mixtures with added N,N,N′,N″,N″-pentamethyldiethylenetriamine (PMDTA) reacts with alkyl halides, epoxides, hydrazones, arenes, alkenes, and allyl ethers. Comparisons of PMDTA with N,N,N′,N′tetramethylethylenediamine (TMEDA) accompanied by detailed rate and computational studies reveal the importance of the trifunctionality and κ 2 −κ 3 hemilability. Rate studies show exclusively monomer-based reactions of 2-bromooctane, cyclooctene oxide, and dimethylresorcinol. Catalysis with 10 mol % PMDTA shows up to >30-fold accelerations (k cat > 300) with no evidence of inhibition over 10 turnovers. Solid−liquid phase-transfer catalysis (SLPTC) is explored as a means to optimize the catalysis as well as explore the merits of heterogeneous reaction conditions.

Highly Reactive Hydrocarbon Soluble Alkylsodium Reagents for Benzylic Aroylation of Toluenes using Weinreb Amides

“…Furthermore, moving to the higher tetradentate donor Me 6 TREN, to form in situ monomeric 1 b , afforded an excellent yield of 86 %, (entry 5). This shows just how important the correct donor choice is to break the organosodium aggregation and to promote its kinetic activation [47, 48] . Bulkier amide NaTMP (entry 6) was less effective at metalating toluene affording 4 a in a 48 % yield.…”

“…This shows just how important the correct donor choice is to break the organosodium aggregation and to promote its kinetic activation. [47,48] Bulkier amide NaTMP (entry 6) was less effective at metalating toluene affording 4 a in a 48 % yield. In this case we observe that some of the sodium amide can also react with 3 a causing its partial degradation.…”

Li vs Na: Divergent Reaction Patterns between Organolithium and Organosodium Complexes and Ligand-Catalyzed Ketone/Aldehyde Methylenation

“…Compared with other popular CH 2 transfer reagents, such as phosphorus ylides (Wittig), sulfones (Julia and Kocieński), titanium (Tebbe), zirconium, rare-earth, molybdenum (Kauffmann), or chromium (Takai) reagents, the organosodium reagent [NaCH 2 SiMe 3 ] ∞ features significant sustainability advantages and, potentially, a much lower cost (for comparison, Tebbe reagent solution (0.5 M in toluene) is priced at £229 for 25 mL at Merck). The concept of ligand-catalysis (and the relevant solvent-catalysis) is based on reversible coordination of a ligand (e.g., Me 6 Tren in this case) to the metal center, which has been seldom reported in Group-1 metal chemistry as early as in the 1960s − until today, − mostly for deprotonation reactions.…”

Enhancing Metalating Efficiency of the Sodium Amide NaTMP in Arene Borylation Applications

“…Repeating the reaction adding TMEDA increased the yield of 2‐iodoanisole to 35 %, in evidence of an increased reactivity of NaTMP upon its deaggregation induced by the Lewis donor. Addition of tridentate PMDETA, which has been cited as a superior donor for NaDA due to its hemilability, [10c] led to almost identical conversions to those for TMEDA (36 %, Figure 1c).…”