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

Abstract

The first facile and efficient copper-catalyzed direct C-P cross-coupling of unprotected propargylic alcohols with P(O)H compounds has been developed, providing a general, one-step approach to construct valuable allenylphosphoryl frameworks with operational simplicity and high step- and atom-economy under ligand-, base-, and additive-free conditions.

Scope and advances in the catalytic propargylic substitution reaction

“…77 The reaction proceeded under mild reaction conditions with high efficiency and excellent regioselectivity. Low yields were only observed when other conventional diamine ligands (111)(112)(113)(114)(115)(116)(117) were used along with the nickel catalyst, Fig. 3.…”

“…In the year 2016, Gao and co-workers also successfully developed similar Cu-catalyzed direct coupling of the unprotected terminal and internal propargylic alcohols 39 with P(O)H compounds 182, Scheme 82 . 112 …”

Synthesis of benzothiophene and indole derivatives through metal-free propargyl–allene rearrangement and allyl migration

“…Consequently, new and straightforward methods to access indoles are highly desirable [ 35 – 36 ]. We chose a propargyl phosphite rearrangement to achieve allenyl intermediates and aimed to synthetize indoles via allenyl phosphonates, which were versatile synthetic intermediates [ 37 – 38 ]. The N -methyl- N -allylpropargyl alcohol 3 was treated with (EtO) 2 PCl under alkaline conditions, then underwent a propargyl phosphite/allenyl phosphonate rearrangement and an intramolecular nucleophilic attack to form the indole moiety, followed by allyl migration ( Scheme 2 ).…”

Cadmium(II) Chloride‐Catalyzed Dehydrative C−P Coupling of Propargyl Alcohols with Diarylphosphine Oxides to Afford Allenylphosphine Oxides

“…(4,4‐Dimethyl‐1‐phenylpenta‐1,2‐dien‐3‐yl)diphenyl phosphine oxide (3 a) . 63.2 mg (yield 85%), prepared from 45.1 mg of 1 a (0.24 mmol) and 40.4 mg of 2 a (0.2 mmol) in 2 mL MeCN.…”