A Quick, Clean and Green Synthesis of Methylenedioxyprecocene and other Chromenes over Basic Montmorillonite K10 Clay

Dintzner MatthewR.. Lyons ThomasW.. Akroush MichaelH.. Wucka Paul. Rzepka AdamT..

<P>On page 787, Table 2 was truncated such that entries 4-7 did not appear. The intact table is as follows:</P>

<TD VALIGN="TOP" COLSPAN="10"> </TD><TD VALIGN="TOP"> Entry </TD><TD VALIGN="TOP"> R¹ </TD><TD VALIGN="TOP"> R² </TD><TD VALIGN="TOP"> R³ </TD><TD VALIGN="TOP"> R⁴ </TD><TD VALIGN="TOP"> R⁵ </TD><TD VALIGN="TOP"> R⁶ </TD><TD VALIGN="TOP" COLSPAN="3"> Product distribution (%)
</TD><TD VALIGN="TOP"></TD><TD VALIGN="TOP"></TD><TD VALIGN="TOP"></TD><TD VALIGN="TOP"></TD><TD VALIGN="TOP"></TD><TD VALIGN="TOP"></TD><TD VALIGN="TOP"></TD><TD VALIGN="TOP"> 9 </TD><TD VALIGN="TOP"> 7 </TD><TD VALIGN="TOP"> Other </TD><TD COLSPAN="20">

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</TD></TR><TR><TD VALIGN="TOP"> 1 </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP" COLSPAN="2"> -O(CH₂)O-
</TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> CH₃ </TD><TD VALIGN="TOP"> 48 (9a) </TD><TD VALIGN="TOP"> 11 </TD><TD VALIGN="TOP"> 41 </TD><TD COLSPAN="20">

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</TD></TR><TR><TD VALIGN="TOP"> 2 </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP" COLSPAN="2"> -O(CH₂)O-
</TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> 7 (9b) </TD><TD VALIGN="TOP"> 10 </TD><TD VALIGN="TOP"> 83 </TD><TD VALIGN="TOP"> 3 </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> OCH₃ </TD><TD VALIGN="TOP"> OCH₃ </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> CH₃ </TD><TD VALIGN="TOP"> CH₃ </TD><TD VALIGN="TOP"> 18 (9c) </TD><TD VALIGN="TOP"> 68 </TD><TD VALIGN="TOP"> 14 </TD><TD VALIGN="TOP"> 4 </TD><TD VALIGN="TOP"> Br </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> CH₃ </TD><TD VALIGN="TOP"> CH₃ </TD><TD VALIGN="TOP"> 84 (9d) </TD><TD VALIGN="TOP"> 6 </TD><TD VALIGN="TOP"> 10 </TD><TD VALIGN="TOP"> 5 </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> CH₃ </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> CH₃ </TD><TD VALIGN="TOP"> CH₃ </TD><TD VALIGN="TOP"> 97 (9e) </TD><TD VALIGN="TOP"> 0 </TD><TD VALIGN="TOP"> 3 </TD><TD VALIGN="TOP"> 6 </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> CH₃ </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> CH₃ </TD><TD VALIGN="TOP"> CH₃ </TD><TD VALIGN="TOP"> 56 (9f) </TD><TD VALIGN="TOP"> 0 </TD><TD VALIGN="TOP"> 44 </TD><TD VALIGN="TOP"> 7 </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> H </TD><TD VALIGN="TOP"> CH₃ </TD><TD VALIGN="TOP"> CH₃ </TD><TD VALIGN="TOP"> 70 (9g) </TD><TD VALIGN="TOP"> 0 </TD><TD VALIGN="TOP"> 30 </TD>

Table 2 Reaction Scope

<P>The editorial office apologizes for the omission.</P><P></P>