2,3-Diazabicyclo[2.2.1]heptane

Abstract

[279-31-2][959680-36-5] C5H10N2 (MW 98.15)

InChI = 1S/C5H10N2/c1-2-5-3-4(1)6-7-5/h4-7H,1-3H2

InChIKey = PWHOCEZDDSHQTI-UHFFFAOYSA-N

(carbonyl-olefin metathesis of cyclopropenes1)

Note: 2,3-diazabicyclo[2.2.1]heptane bis-hydrochloride has been synthesized and is stable relative to 2,3-diazabicyclo[2.2.1]heptane (free hydrazine). Data for both compounds will be included.

Alternate Names: 2,3-diaza-norbornane.

Physical Data: free hydrazine: mp 53°C.2

Solubility: Free hydrazine: soluble in most organic solvents (Et2O, C6H6, MeOH, CHCl3). Bis-hydrochloride salt: soluble in DMSO and MeOH, soluble in DCE at 70°C.

Form Supplied in: both the free hydrazine and the bis-hydrochloride salt are white solids.

Analysis of Reagent Purity: Free hydrazine: 1H-NMR (C6D6) δ 3.14 (s, 2H), 3.04 (br s, 2H), 1.26 (s, 2H), 1.23–1.16 (m, 4H).3 Bis-hydrochloride salt: 1H-NMR (d6-DMSO) δ 6.7 (br s, 2H), 3.94 (s, 2H), 1.78–1.67 (m, 6H).1

Preparative Methods: a Diels–Alder reaction with cyclopentadiene and the corresponding azodicarboxylate yields the bicyclic hydrazine core (eq 1). Subsequent hydrogenation and hydrolysis yield the free hydrazine (basic hydrolysis)4 or the bis-hydrochloride salt (acidic hydrolysis).1

rn01779es.001
(1)
Purification: the bis-hydrochloride salt can be used without further purification, but may be recrystallized from hot EtOH/hexanes.

Handling, Storage, and Precautions: Free hydrazine: readily oxidized in air and highly hygroscopic.5 Difficult to maintain purity. Bis-hydrochloride salt: somewhat hygroscopic. Stored under air in a dry box over several weeks.