tert-Butyl (E)-3-oxo-2-(3-oxoisobenzofuran-1(3H)-ylidene)butanoate
Round 1
Reviewer 1 Report
“tert-Butyl (E)-3-oxo-2-(3-oxoisobenzofuran-1(3H)-ylidene)butanoate”
The article describes the synthesis and characterization of tert-Butyl (E)-3-oxo-2-(3-oxoisobenzofuran-1(3H)-ylidene)butanoate from phthalic anhydride and tert-butyl acetoacetate in high yield through mild conditions. The authors demonstrated that this newly synthesized compound is an effective intermediate in the synthesis of 1H-indene-1,3(2H)-dione.
In general, the manuscript is well written, and the introduction is adequate to the described compound. The experimental procedure is clear, and the characterization data is in accordance with the synthesized compound. However, there are a few aspects that may be improved.
In the results and discussion, the reaction time and the yield of compound 1 is not mentioned. Once the article describes, for the first time, the synthesis of compound 1 these two reaction details should be included in Scheme 2 and in the text. Moreover, the yield of 1H-indene-1,3(2H)-dione may be also included in the scheme.
In the 1H NMR description of compound 1, the values of the J are separated by “,” and should be “.”.
The HRMS-ESI calculated for C16H16O5 (288.0998) is not correct. Using electrospray ionization (ESI) the molecular ion observed is [M+H+]. So, the formula should be correct to C16H17O5, by this way the values are correct.
The reference 21 don’t describe the melting point of 1H-indene-1,3(2H)-dione. Should be correct.
The spectrum given in Figure S4 (Supplementary Material) don’t belongs to a COSY spectrum. Replace the spectrum.
Author Response
Reviewer 1
The authors are grateful to the reviewer for a kind and highly professional review.
Point 1.
In the results and discussion, the reaction time and the yield of compound 1 is not mentioned. Once the article describes, for the first time, the synthesis of compound 1 these two reaction details should be included in Scheme 2 and in the text. Moreover, the yield of 1H-indene-1,3(2H)-dione may be also included in the scheme.
Response from authors.
The reaction time and the yields of compound 1 and 1H-indene-1,3(2H)-dione are included in the text and in Scheme 2.
Point 2.
In the 1H NMR description of compound 1, the values of the J are separated by “,” and should be “.”.
Response from authors.
Corrected as suggested by the reviewer.
Point 3.
The HRMS-ESI calculated for C16H16O5 (288.0998) is not correct. Using electrospray ionization (ESI) the molecular ion observed is [M+H+]. So, the formula should be correct to C16H17O5, by this way the values are correct.
Response from authors.
Corrected as suggested by the reviewer.
Point 4.
The reference 21 don’t describe the melting point of 1H-indene-1,3(2H)-dione. Should be correct.
Response from authors.
Reference 21, which describes the melting point of 1H-indene-1,3(2H)-dione, has been changed to the correct one.
Point 5.
The spectrum given in Figure S4 (Supplementary Material) don’t belongs to a COSY spectrum. Replace the spectrum.
Response from authors.
The spectrum in Figure S4 (Supplementary Material) has been replaced.