Room-Temperature Metal-Catalyzed Hydrogen Borrowing Alkylation.

Area of Science:

• Organic Chemistry
• Catalysis
• Sustainable Chemistry

Background:

• Hydrogen borrowing reactions offer a sustainable alternative to traditional alkylation using alkyl halides.
• Alcohols are abundant, stable, and greener alkylating agents, producing only water as a byproduct.
• Most reported hydrogen borrowing reactions require high temperatures (76-200 °C), limiting their applicability.

Purpose of the Study:

• To review the current state of room-temperature (≤30 °C) hydrogen borrowing reactions.
• To highlight advancements in both carbon-carbon (C-C) and carbon-nitrogen (C-N) bond formation via hydrogen borrowing at ambient temperatures.
• To provide a comprehensive overview of low-temperature catalytic strategies in organic synthesis.

Main Methods:

• Literature review of recent studies on hydrogen borrowing reactions.
• Focus on reactions conducted at or below 30 °C.
• Analysis of catalytic systems, reaction conditions, and substrate scope for C-C and C-N bond formation.

Main Results:

• Significant progress has been made in developing efficient hydrogen borrowing reactions at room temperature.
• Successful examples of room-temperature C-C and C-N bond formation using various catalytic systems have been reported.
• These low-temperature methods offer improved selectivity and reduced energy consumption compared to high-temperature protocols.

Conclusions:

• Room-temperature hydrogen borrowing is a viable and increasingly important strategy in modern organic synthesis.
• Further research into catalytic systems and reaction optimization can expand the scope and efficiency of these reactions.
• This approach aligns with green chemistry principles by minimizing energy input and waste generation.