Diphenylethine

Structural formula
General
Surname	Diphenylethine
other names	Tolan Diphenylacetylene 2-phenylethynylbenzene ( IUPAC )
Molecular formula	C 14 H 10
Brief description	white needles
External identifiers / databases
CAS number 501-65-5 EC number 207-926-6 ECHA InfoCard 100.007.206 PubChem 10390 Wikidata Q902100
properties
Molar mass	178.23 g mol −1
Physical state	firmly
density	0.99 g cm −3 (25 ° C)
Melting point	59-61 ° C
safety instructions
GHS labeling of hazardous substances no GHS pictograms H and P phrases H: no H-phrases P: no P-phrases
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Diphenylethine is the chemical compound C ₆ H ₅ –C≡C – C ₆ H ₅ . The molecule consists of two phenyl radicals that are bound to both ends of an alkynic triple bond. The compound can therefore be regarded as both an ethine derivative and a benzene derivative .

Diphenylethine is a colorless crystalline solid that is widely used both as a basic building block in organic synthesis and as a ligand in organometallic chemistry .

Manufacturing

Diphenylethine can be made in several ways:

• Condensation of benzil with hydrazine yields the dihydrazone, which is then oxidized with mercury (II) oxide .
• Bromination of stilbene (diphenylethene) and subsequent dehydrohalogenation. However, the product can be contaminated with difficult to separate stilbene.
• Stephens-Castro coupling of iodobenzene with the copper salt of phenylethine.

Significant derivatives

• Reaction with tetraphenylcyclopentadienone yields hexaphenylbenzene .
• The reaction with benzal chloride in the presence of potassium tert -butanolate gives the 3-alkoxy cyclopropene , which is converted in hydrogen bromide to triphenylcyclopropenium bromide.

Individual evidence

1. ↑ ^{a b} Lee Irvin Smith, MM Falkof: diphenylacetylenes In: Organic Synthesis . 22, 1942, p. 50, doi : 10.15227 / orgsyn.022.0050 ; Coll. Vol. 3, 1955, p. 350 ( PDF ).
2. ↑ ^{a b c d} Data sheet Diphenylacetylene, 98% from Sigma-Aldrich , accessed on May 10, 2012 ( PDF ).
3. ^ ^{A b} Arthur C. Cope, Douglas S. Smith, Robert J. Cotter: Diphenylacetylene In: Organic Syntheses . 34, 1954, p. 42, doi : 10.15227 / orgsyn.034.0042 ; Coll. Vol. 4, 1963, p. 377 ( PDF ).
4. ↑ Louis F. Fieser: Hexaphenylbenzene In: Organic Syntheses . 46, 1966, p. 44, doi : 10.15227 / orgsyn.046.0044 ; Coll. Vol. 5, 1973, p. 604 ( PDF ).
5. ↑ Ruo Xu, Ronald Breslow: 1,2,3-Triphenylcyclopropendium Bromide In: Organic Syntheses . 74, 1997, p. 72, doi : 10.15227 / orgsyn.074.0072 ; Coll. Vol. 9, 1998, p. 730 ( PDF ).