Bis(trimethylsilyl)acetylene

Chemical properties

clear colorless liquid after melting

The Uses of Bis(trimethylsilyl)acetylene

In the presence of CpCo(CO)2 (cat. no. 245259), undergoes cycloaddition with 1,5-hexadiynes to form benzocyclobutenes.1

The Uses of Bis(trimethylsilyl)acetylene

BTMSA is used as starting reagent in the synthesis of functionalized 4-R-1,2-bis(trimethylsilyl)benzenes. It is also used in the synthesis of (+)-brasilenyne2 and (β-diketanato)Ag(BTMSA). Bis(trimethylsilyl)acetylene is a ligand that binds to a central metal ion (e.g. Titanium) to create a coordination complex. One of its complexes, Permethyltitanocene-bis(trimethylsilyl)acetylene, is a catalyst for the head-to-tail dimerization of 1-alkynes (e.g. 3-Penten-1-yne [P227430]).

General Description

Bis(trimethylsilyl)acetylene (BTMSA) participates as nucleophile in Friedel-Crafts type acylations and alkylations. BTMSA undergoes rhodium catalyzed addition reaction with diarylacetylenes. It undergoes cycloaddition with 1,5-hexadiynes in the presence of CpCo(CO)₂ (Cp=cyclopentadienyl) to form benzocyclobutenes. Structure of BTMSA was characterized by a centre of inversion present on triple bond (length=1.208(3)?). TiCl₄-Et₂AlCl catalyzed Diels-Alder reaction of BTMSA with norbornadiene has been reported.

Purification Methods

Dissolve it in pet ether and wash it with ice-cold dilute HCl. The pet ether extract is dried (MgSO4), evaporated and fractionated at 760mm. [Walton & Waugh J Organomet Chem 37 45 1972, Beilstein 4 IV 3950.]