Prev. Article Next Article Table of Contents

Communication

Alkali Metals Plus Silica Gel: Powerful Reducing Agents and Convenient Hydrogen Sources

Supporting Info

James L. Dye,*^†^‡ Kevin D. Cram,^† Stephanie A. Urbin,^† Mikhail Y. Redko,^† James E. Jackson,^† and Michael Lefenfeld*^‡;

Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, and SiGNa Chemistry, LLC, 530 East 76th Street, Suite 9E, New York, New York 10021

J. Am. Chem. Soc., 2005, 127 (26), pp 9338–9339

DOI: 10.1021/ja051786+

Publication Date (Web): June 14, 2005

In papers with more than one author, the asterisk indicates the name of the author to whom inquiries about the paper should be addressed.

†

Michigan State University.

‡

SiGNa Chemistry, LLC.

dye@signachem.com; michael@signachem.com

Abstract

Alkali metals absorbed into silica gel yield three stages of unique loose black powders (M−SG) that are strong reducing agents. All react nearly quantitatively with water to form hydrogen. Liquid Na−K alloys form air-sensitive powders at room temperature that can be converted at 150 °C to a form that is sensitive to moisture but not to dry air. Slowly heating sodium and silica gel to 400 °C yields a third type that can be handled in ambient air with only slow degradation by atmospheric moisture. These materials eliminate many hazards associated with pure alkali metals and provide easily handled reducing agents and hydrogen sources. They could be used in continuous-flow reactors to reduce and protonate aromatics, dechlorinate alkyl and aryl halides, and desulfurize various compounds.

View: Full Text HTML | Hi-Res PDF