3-Imidoallenylphosphonates: In Situ Formation and β-Alkoxylation

Abstract

3-Imidoallenylphosphonates, allenes bearing both an electron-withdrawing and -donating group, were isolated for the first time. An alkoxy substituent was introduced into these unprecedented intermediates in a one-pot approach, yielding β-functionalized aminophosphonates in excellent yields and short reaction times. The mechanistic insights gained are important additions to the domain of allene chemistry. Addition of biologically important molecules, including monoglycerides, amino acids, and nucleosides, proves the general applicability of the developed method.

Three-Step Synthesis of Chiral Spirocyclic Oxaphospholenes

“…The outstanding characteristics of BINOL phosphates to control enantioselectivities originate from the phosphorus-containing seven-membered ring and the chiral binaphthyl moiety, locking the conformation of the Brønsted acid function. 10 Inspired by our expertise in oxaphospholene chemistry, 11−13 the synthesis of phosphorus-containing allenes 14,15 and heterocycles, 16−18 we envisioned the synthesis of chiral spirocyclic oxaphospholenes 4, which may be of interest for the design of new chiral phosphonic acid catalysts. Moreover, oxaphospholenes have attracted the interest of synthetic chemists for half a century already, and they have been investigated for their fungistatic, antiviral, and antioxidant activities.…”

“…Inspired by our expertise in oxaphospholene chemistry, − the synthesis of phosphorus-containing allenes , and heterocycles, − we envisioned the synthesis of chiral spirocyclic oxaphospholenes 4 , which may be of interest for the design of new chiral phosphonic acid catalysts. Moreover, oxaphospholenes have attracted the interest of synthetic chemists for half a century already, and they have been investigated for their fungistatic, antiviral, and antioxidant activities .…”

Copper-Catalyzed Direct Coupling of Unprotected Propargylic Alcohols with P(O)H Compounds: Access to Allenylphosphoryl Compounds under Ligand- and Base-Free Conditions

“…Further, allenes have attracted continuous attention over the past few decades due to their unique cumulene structure and unusual biological activities . Among them, allenylphosphoryl compounds including allenyl phosphonates, phosphinates, and phosphine oxides are an important class of allene-containing, extremely versatile reagents in organic chemistry, especially for the preparation of structurally diverse organophosphorus compounds including useful chiral phosphorus compounds and phosphorus heterocycles of pharmaceutical interest via selective addition with various electrophiles or nucleophiles, selective total or partial hydrogenation, radical reactions, Diels–Alder reaction, or other cycloadditions . In addition, some allenylphosphoryl compounds are endowed with interesting biological activities .…”