Synthesis of α‐Diazo Carbonyl Compounds with the Shelf‐Stable Diazo Transfer Reagent Nonafluorobutanesulfonyl Azide

Abstract

Nonafluorobutanesulfonyl azide is a shelf-stable, cost-effective and general diazo transfer reagent for the efficient synthesis of a-diazo carbonyl compounds in excellent yields and in very short reaction times, under mild conditions. The diazo products can be readily isolated in pure form after a simple aqueous extractive work-up that avoids chromatographic purification in most cases. Because of its high efficiency and wide substrate scope, shelf-stability, relatively low cost, and ease of product purification, nonafluorobutanesulfonyl azide offers an advantageous alternative to other commonly used diazo transfer reagents.

λ5-Phosphorus-Containing α-Diazo Compounds: A Valuable Tool for Accessing Phosphorus-Functionalized Molecules

“…However, as a valid alternative, numerous sulfonyl azides have been developed for the synthesis of PCDCs. These azides were reported to be superior to tosyl azide in terms of stability, safety, and product purification. ,− Among them, triflyl azide was shown to be essential for the successful transformation of the nitrophosphonate 41 into diethyl [nitro­(diazo)­methyl] phosphonate ( 42 ) (Scheme ).…”

Urea Activation of α-Nitrodiazoesters: An Organocatalytic Approach to N–H Insertion Reactions

“…Ethyl nitrodiazoacetate was synthesized following a known procedure. 5 To a flamedried 50 mL round bottom flask containing a stirbar was added ethyl nitroacetate (2.89 mL, 26.0 mmol) and dichloromethane (10 mL) under Ar. The flask was cooled to 0 ºC and 2,6-lutidine (4.24 mL, 36.4 mmol) was added, followed by NfN 3 (9.30 g, 28.6 mmol).…”

“…While we were motivated by the promise of HBD-catalyzed N–H insertion methodologies, the project was initiated with a significant amount of uncertainty as to whether a urea could aid in the decomposition of a diazo compound. The assessment of this approach began with studies of the urea-catalyzed insertion of α-diazo-α-nitro ester 5 into the N–H bond of aniline ( 6 , Table ).…”

Synthesis of N,N′‐Disulfonylamidines from Sulfonamides and Alkynes by a Two‐Step, One‐Pot Reaction with Nonafluorobutanesulfonyl Azide

“…We and others have recently shown that nonafluorobutanesulfonyl azide (nonaflyl azide: NfN 3 ) is an efficient, shelf‐stable and cost‐effective24 diazo transfer reagent for the synthesis of azides from primary amines25 and for the preparation of α‐diazo carbonyl compounds 26. We have now explored the use of NfN 3 for the synthesis of sulfonyl azides from readily available sulfonamides and the application of this reaction in a novel copper‐catalyzed two‐step, one‐pot sequential process with added terminal alkynes to afford N , N′ ‐disulfonylamidines.…”