From Wikipedia, the free encyclopedia
Pinacolborane
Names
Preferred IUPAC name
4,4,5,5-Tetramethyl-1,3,2-dioxaborolane
Other names
HBpin
Identifiers
ChemSpider
ECHA InfoCard
100.118.700
EC Number
InChI=1S/C6H12BO2/c1-5(2)6(3,4)9-7-8-5/h1-4H3
Key: LZPWAYBEOJRFAX-UHFFFAOYSA-N
Properties
C 6 H 13 B O 2
Molar mass
127.98 g·mol−1
Appearance
colorless liquid
Density
0.882 g/cm3
Boiling point
42–43 °C (108–109 °F; 315–316 K) 50 mmHg
Hazards
GHS labelling :
Danger
H220 ,
H225 ,
H260 ,
H261 ,
H315 ,
H318
P210 ,
P223 ,
P231+P232 ,
P233 ,
P240 ,
P241 ,
P242 ,
P243 ,
P264 ,
P280 ,
P302+P352 ,
P303+P361+P353 ,
P305+P351+P338 ,
P310 ,
P321 ,
P332+P313 ,
P335+P334 ,
P362 ,
P370+P378 ,
P377 ,
P381 ,
P402+P404 ,
P403 ,
P403+P235 ,
P501
Except where otherwise noted, data are given for materials in their
standard state (at 25 °C [77 °F], 100 kPa).
Chemical compound
Pinacolborane is the
borane with the formula (CH3 )4 C2 O2 BH. Often pinacolborane is abbreviated HBpin.
[1] It features a boron hydride functional group incorporated in a five-membered C2 O2 B ring. Like related boron
alkoxides , pinacolborane is monomeric. It is a colorless liquid.
[2] It features a reactive B-H functional group.
[3]
Use in organic synthesis
In the presence of catalysts, pinacolborane
hydroborates alkenes and, less rapidly, alkynes.
[3]
[4]
Pinacolborane also affects catalyst-free hydroboration of aldehydes,
[5] ketones,
[6] and carboxylic acids.
[7]
Pinacolborane is used in
borylation , a form of
C-H activation .
[8]
[9]
Dehydrogenation of pinacolborane affords
dipinacolatodiborane (B2 pin2 ):
[10]
2 (CH3 )4 C2 O2 BH → (CH3 )4 C2 O2 B-BO2 C2 (CH3 )4 + H2
Related compounds
References
^
"4,4,5,5-Tetramethyl-1,3,2-dioxaborolane" .
^ Ramachandran, P. Veeraraghavan; Chandra, J. Subash; Ros, Abel; Fernández, Rosario; Lassaletta, José M.; Aggarwal, Varinder K.; Blair, Daniel J. (2017). "Pinacolborane". Encyclopedia of Reagents for Organic Synthesis . pp. 1–12.
doi :
10.1002/047084289X.rn00574.pub3 .
ISBN
9780470842898 .
^
a
b Brown, H.C.; Zaidlewicz, M. (2001). Organic Syntheses Via Boranes, Vol. 2 . Milwaukee, WI: Aldrich Chemical Co.
ISBN
978-0-9708441-0-1 .
^ Ely, Robert J.; Morken, James P. (2011).
"Stereoselective Nickel-Catalyzed 1,4-Hydroboration of 1,3-Dienes" . Organic Syntheses . 88 : 342.
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^ Stachowiak, Hanna; Kaźmierczak, Joanna; Kuciński, Krzysztof; Hreczycho, Grzegorz (2018). "Catalyst-free and solvent-free hydroboration of aldehydes". Green Chemistry . 20 (8): 1738–1742.
doi :
10.1039/C8GC00042E .
ISSN
1463-9262 .
^ Wang, Weifan; Luo, Man; Yao, Weiwei; Ma, Mengtao; Pullarkat, Sumod A.; Xu, Li; Leung, Pak-Hing (2019). "Catalyst-free and solvent-free hydroboration of ketones". New Journal of Chemistry . 43 (27): 10744–10749.
doi :
10.1039/C9NJ02722J .
ISSN
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S2CID
197130591 .
^ Harinath, Adimulam; Bhattacharjee, Jayeeta; Panda, Tarun K. (2019). "Facile Reduction of carboxylic acids to primary alcohols under catalyst-free and solvent-free conditions". Chemical Communications . 55 (10): 1386–1389.
doi :
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ISSN
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PMID
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S2CID
58570916 .
^ Amaike, K.; Loach, R. P.; Movassaghi, M. (2015).
"Direct C7 Functionalization of Tryptophan. Synthesis of Methyl (S )-2-((tert -Butoxycarbonyl)amino)-3-(7-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H -indol-3-yl)propanoate" (PDF) . Organic Syntheses . 92 : 373–385.
doi :
10.15227/orgsyn.092.0373 .
PMC
4733874 .
PMID
26839440 .
^ Ishiyama, Tatsuo; Takagi, Jun; Nobuta, Yusuke;
Miyaura, Norio (2005). "Iridium-Catalyzed C-H Borylation of Arenes and Heteroarenes: 1-Chloro-3-Iodo-5-(4,4,5,5-Tetramethyl-1,3,2-Dioxaborolan-2-Yl)Benzene and 2-(4,4,5,5,-Tetramethyl-1,3,2-Dioxaborolan-2-Yl)Indole". Organic Syntheses . 82 : 126.
doi :
10.15227/orgsyn.082.0126 .
hdl :
2115/56319 .
^ Neeve, Emily C.; Geier, Stephen J.; Mkhalid, Ibraheem A. I.; Westcott, Stephen A.; Marder, Todd B. (2016).
"Diboron(4) Compounds: From Structural Curiosity to Synthetic Workhorse" . Chemical Reviews . 116 (16): 9091–9161.
doi :
10.1021/acs.chemrev.6b00193 .
hdl :
1807/78811 .
PMID
27434758 .