N-Hydroxyphthalimide → Di-tert-butyl [{4-[(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)oxy]piperidin-1-yl}methylylidene]biscarbamate

Participants

Role	Name	HCID	Charge
Reactant	N-Hydroxyphthalimide	HCID 10665	—
Reactant	Triphenylphosphine	HCID 11776	—
Reactant	Diisopropyl diazene-1,2-dicarboxylate	HCID 75555	—
Reactant	[Tert-butoxycarbonylimino-(4-hydroxy-piperidin-1-yl)-methyl]-carbamic acid tert-butyl ester	HCID 67271828	—
Solvent	Tetrahydrofuran	HCID 8028	—
Product	Di-tert-butyl [{4-[(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)oxy]piperidin-1-yl}methylylidene]biscarbamate	HCID 86699594	31.7%

Reaction Steps

To a mixture of N-hydroxyphthalimide (1.89 g, 11.62 mmol), di-tert-butyl[(4-hydroxypiperidin-1-yl)methylylidene]biscarbamate 63 (2.00 g, 5.81 mmol, US 2004/209921 A1) and triphenylphosphine (3.05 g, 11.62 mmol) in THF (100 mL) was added diisopropyl azodicarboxylate (2.47 mL, 12.78 mmol) slowly at room temperature. The resulting mixture was stirred at room temperature overnight and concentrated to provide a residue which was subjected to chromatography to give 64 (0.9 g) as a white solid.

Provenance & Evidence

DOI	10.6084/m9.figshare.5104873.v1
Patent number	US08796257B2
Source dataset	uspto-grants-2014_08
ORD ID	ord-aa734fadc28a4030a418e51e11f3c2ca
Source note	uspto-grants-2014_08