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Chemistry of [(1H-hydronaphthalene)Mn(CO)<INF>3</INF>]:  The Role of Ring-Slippage in Substitution, Catalytic Hydrosilylation, and Molecular Crystal Structure of [(η<SUP>3</SUP>-C<INF>10</INF>H<INF>9</INF>)Mn(CO)<INF>3</INF>P(OMe)<INF>3</INF>]

Authors :
Son, S. U.
Paik, S.-J.
Lee, I. S.
Lee, Y.-A
Chung, Y. K.
Seok, W. K.
Lee, H. N.
Source :
Organometallics; September 27, 1999, Vol. 18 Issue: 20 p4114-4118, 5p
Publication Year :
1999

Abstract

Reaction of [(η&lt;SUP&gt;5&lt;/SUP&gt;-C&lt;INF&gt;10&lt;/INF&gt;H&lt;INF&gt;9&lt;/INF&gt;)Mn(CO)&lt;INF&gt;3&lt;/INF&gt;] (&lt;BO&gt;1&lt;/BO&gt;) with L produced [(η&lt;SUP&gt;3&lt;/SUP&gt;-C&lt;INF&gt;10&lt;/INF&gt;H&lt;INF&gt;9&lt;/INF&gt;)Mn(CO)&lt;INF&gt;3&lt;/INF&gt;L] (&lt;BO&gt;2&lt;/BO&gt;, L = P(OMe)&lt;INF&gt;3&lt;/INF&gt;; &lt;BO&gt;5&lt;/BO&gt;, L = CO) in high yields. X-ray structural analysis of &lt;BO&gt;2&lt;/BO&gt; confirmed an η&lt;SUP&gt;3&lt;/SUP&gt;-bonding mode of the 1-hydronaphthalene ring. Thermal treatment of &lt;BO&gt;2&lt;/BO&gt; led to [(η&lt;SUP&gt;5&lt;/SUP&gt;-C&lt;INF&gt;10&lt;/INF&gt;H&lt;INF&gt;9&lt;/INF&gt;)Mn(CO)&lt;INF&gt;2&lt;/INF&gt;P(OMe)&lt;INF&gt;3&lt;/INF&gt;] (&lt;BO&gt;3&lt;/BO&gt;). The η&lt;SUP&gt;5&lt;/SUP&gt;-1-hydronaphthalene ring in &lt;BO&gt;1&lt;/BO&gt; is quite easily ring-slipped, η&lt;SUP&gt;5&lt;/SUP&gt; ↔ η&lt;SUP&gt;3&lt;/SUP&gt;. A kinetic study of the reaction of &lt;BO&gt;1&lt;/BO&gt; with P(OMe)&lt;INF&gt;3&lt;/INF&gt; indicates that formation of &lt;BO&gt;2&lt;/BO&gt; is first order in &lt;BO&gt;1&lt;/BO&gt; and first order in P(OMe)&lt;INF&gt;3&lt;/INF&gt; with the following activation parameters:  ΔH&lt;SUP&gt;&amp;thermod;&lt;/SUP&gt; = 6.9 &#177; 0.4 kcal/mol; ΔS&lt;SUP&gt;&amp;thermod;&lt;/SUP&gt; = −32.6 &#177; 1.5 eu. Quantitative comparison between the reactivity of the indenyl complex [(η&lt;SUP&gt;5&lt;/SUP&gt;-C&lt;INF&gt;9&lt;/INF&gt;H&lt;INF&gt;7&lt;/INF&gt;)Mn(CO)&lt;INF&gt;3&lt;/INF&gt;] with P(OEt)&lt;INF&gt;3&lt;/INF&gt; and &lt;BO&gt;1&lt;/BO&gt; with P(OMe)&lt;INF&gt;3&lt;/INF&gt; at 130 &#176;C shows that the rate constant for &lt;BO&gt;1&lt;/BO&gt; is 2 &#215; 10&lt;SUP&gt;6&lt;/SUP&gt; times faster than that of the indenyl complex. The tremendous rate enhancement in &lt;BO&gt;1&lt;/BO&gt; was rationalized as a stabilization of &lt;BO&gt;2&lt;/BO&gt; by the second benzene ring. The facile ring-slippage in &lt;BO&gt;1&lt;/BO&gt; has been utilized in the synthesis of [(η&lt;SUP&gt;6&lt;/SUP&gt;-C&lt;INF&gt;10&lt;/INF&gt;H&lt;INF&gt;8&lt;/INF&gt;)Mn(CO)&lt;INF&gt;2&lt;/INF&gt;P(OMe)&lt;INF&gt;3&lt;/INF&gt;]BF&lt;INF&gt;4&lt;/INF&gt; and in the catalytic hydrosilylation of ketones. Complex&lt;BO&gt; 1 &lt;/BO&gt;is an effective catalyst for the hydrosilylation of alkyl and aryl ketones with Ph&lt;INF&gt;2&lt;/INF&gt;SiH&lt;INF&gt;2&lt;/INF&gt; as a silane source. The indenyl complex [(η&lt;SUP&gt;5&lt;/SUP&gt;-C&lt;INF&gt;9&lt;/INF&gt;H&lt;INF&gt;7&lt;/INF&gt;)Mn(CO)&lt;INF&gt;3&lt;/INF&gt;] has no catalytic activity in the hydrosilylation of ketones. The facile ring-slippage in the η&lt;SUP&gt;5&lt;/SUP&gt;-1-hydronaphthalene ring plays a crucial role in the chemistry of &lt;BO&gt;1&lt;/BO&gt;.

Details

Language :
English
ISSN :
02767333 and 15206041
Volume :
18
Issue :
20
Database :
Supplemental Index
Journal :
Organometallics
Publication Type :
Periodical
Accession number :
ejs1154194

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