Metalation of alkynes. 4. The methoxymercuration reaction

Journal Article · Fri Dec 08 04:00:00 EST 1989 · Journal of Organic Chemistry; (USA)

DOI:https://doi.org/10.1021/jo00286a027· OSTI ID:7071327

Bassetti, M; Floris, B; Spadafora, G ^[1]

---

1. Universita La Sapienza, Roma (Italy)

Methoxymercuration of symmetrically and unsymmetrically substituted alkynes (4-octyne, 2-heptyne, 2-nonyne, 1,4-dimethoxy-2-butyne, 1,4-diacetoxy-2-butyne, methyl 2-octynoate, methyl phenylpropynoate, 1-phenylpropyne, 1-phenyl-1-pentyne, diphenylethyne) was investigated. The corresponding {alpha}-mercurated enol ethers were generally isolated and characterized, except for 4-octyne, 2-heptyne, and 2-nonyne, which yielded {alpha}-acetoxymercurio ketones. Methoxymercuration was investigated kinetically. The rate law is second order, first order in both alkyne and mercuric acetate. Arylalkynes are less reactive than alkyl derivatives and the reaction rate is decreased by electron-withdrawing substituents. Activation parameters were determined for selected substrates. The kinetic data are in agreement with an electrophilic associative rate-determining step. Product analysis results suggest the formation of a cationic intermediate, the nature of which may vary from an unsymmetrically bridged species to an open carbocation, depending on the substrate.

• OSTI ID: 7071327
• Journal Information: Journal of Organic Chemistry; (USA), Journal Name: Journal of Organic Chemistry; (USA) Vol. 54:25; ISSN JOCEA; ISSN 0022-3263
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360101 -- Metals & Alloys-- Preparation & Fabrication
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ALKYNES
ALLOYS
DATA
DATA ANALYSIS
EXPERIMENTAL DATA
HYDROCARBONS
INFORMATION
KINETICS
MEASURING INSTRUMENTS
MEASURING METHODS
MERCURY ADDITIONS
MERCURY ALLOYS
NUMERICAL DATA
ORGANIC COMPOUNDS