實 驗

DEPT實驗分為 DEPT-45,  DEPT-90,  DEPT-135

DEPT-45 可偵測到 一、二、三級碳的訊號

DEPT-90  可偵測到 三級碳的訊號

DEPT-135 可偵測到 一、三級碳的訊號為正 ，並偵測到二級碳的訊號為負。

相 位

碳峰之正負方向靠相位調整完成；向上為正，向下為負。

對於 DEPT 實驗，一般會將CH，CH3 調為正向，CH2調為負向。

DEPT實驗配合一般碳譜就可分辨出碳的級數。

製 圖

一般而言，會將13C與DEPT 譜置於同一張圖譜，方便編輯及判圖。

數據處理時，需注意

(1)各子圖之(sr) 標準點需一致。

(2)DEPT - 90 中出現之峰 (三級碳) 高度需調整 與 DEPT-135(三級碳)相同。

(3)各子圖之左右邊界、坐標點 及長度都需一致。

(4)製圖時，一般碳譜置於最下方，DEPT-45次之，DEPT-90及DEPT-135 依序排列上去。(沒有測的，請忽略之)

(5)完成時，須檢查整組圖碳峰之相位與級數是否一致無誤。

注意: 測完13C及DEPT,  即使結構不詳，

也能編輯出那些是1級 2級及3級碳，

畫完圖時，請自行檢查碳的編輯是否沒有矛盾 

Experiment

DEPT experiments are divided into DEPT-45, DEPT-90, and DEPT-135:

• DEPT-45 can detect signals of primary, secondary, and tertiary carbons.

• DEPT-90 can detect signals of tertiary carbons.

• DEPT-135 can detect signals of primary and tertiary carbons as positive, and signals of secondary carbons as negative.

Phase

The positive or negative direction of the carbon peaks is adjusted by phase; upward is positive, downward is negative. For DEPT experiments, generally CH and CH3 are adjusted to be positive, and CH2 is adjusted to be negative. The DEPT experiment, combined with a regular carbon spectrum, can distinguish the types of carbons.

Charting

Generally, 13C and DEPT spectra are placed on the same chart for easier editing and interpretation. During data processing, note the following:

1. The standard points (sr) of each subplot should be consistent.

2. The height of the peaks (tertiary carbons) in DEPT-90 should be adjusted to match those in DEPT-135 (tertiary carbons).

3. The left and right boundaries, coordinates, and lengths of each subplot should be consistent.

4. When charting, the general carbon spectrum is placed at the bottom, followed by DEPT-45, then DEPT-90, and DEPT-135 in order (ignore those not measured).

5. Upon completion, check that the phase and type of carbon peaks are consistent and correct across the entire set of spectra.

Note: After measuring 13C and DEPT, even if the structure is unknown, you can identify primary, secondary, and tertiary carbons. When the chart is completed, check for any contradictions in the editing of the carbons.

13C + DEPT 製圖要點

1,  每個圖基線得清楚可見  

2,  每支碳都是特別，其强度(峰之高度)不太一樣

3,  DEPT90 中的13C其强度(intensity)應比照 DEPT135的强度

4,   DEPT135的基線應置於圖框的中間，才能見到負向的峰

5,  相位需調成吸收型(absorption) 而非分散型(dispersion)，即峰的左 

       邊及右邊在同一水平線上

6  三組圖的reference (sr) 需一致

7,  三組圖的對應峰其强度(intensity) 應一致。

8,  三組圖的端點(offset) 需一致。

基線   :  baseline  圖譜底線                       

端點   :  offset  圖譜起訖座標點

負向峰 :  negative peak  基線以下之峰

參數表 :  parameter set  實驗條件表

强度   :  intensity  y 軸高度

Key Points for 13C + DEPT Charting

1. The baseline of each spectrum must be clearly visible.

2. Each carbon signal is unique, and their intensities (peak heights) are not the same.

3. The intensity of the 13C peaks in DEPT-90 should match the intensity in DEPT-135.

4. The baseline of DEPT-135 should be placed in the center of the frame to display the negative peaks clearly.

5. The phase should be adjusted to absorption mode rather than dispersion mode, meaning the left and right sides of the peaks should be on the same horizontal line.

6. The reference (sr) for the three sets of spectra should be consistent.

7. The intensity of corresponding peaks in the three sets of spectra should be consistent.

8. The offsets (starting and ending coordinates) of the three sets of spectra should be consistent.

Glossary:

• Baseline: The bottom line of the spectrum.

• Offset: The starting and ending coordinate points of the spectrum.

• Negative Peak: Peaks that are below the baseline.

• Parameter Set: The table of experimental conditions.

• Intensity: The height of the y-axis.

These guidelines ensure clarity and consistency when analyzing and interpreting the 13C and DEPT spectra together.

DEPT的畫法及常見錯誤

1）一般NMR 中 DEPT的畫法是有秩序的。13C在最下方、然後按順序上來是DEPT45,  DEPT90及置於在最頂端的 DEPT135。

2）每個圖譜的各種峰（不包含溶劑峰)都不能超出框的呎規、就是每種13C的高度不會是齊高、而是錯落有致。

3）DEPT 圖中的每一支峰必須是吸收型、而不是分散型、意即峰的底部正就是正、負就是負、正負不能混雜、可將峰垂直拉高放大並檢視      左右基線、調整後恢復正常的高度。正負是相對於基線（baseline ）而言。

4）注意DEPT90 整體的高度需要參考其他圖，讓全部的圖譜在同一張紙上看起來有一致性，而非某一組高度特別的突兀。

5）DEPT135 測出來的相位有正相也有負相，製圖時應將基線（baseline) 置於它所屬的框架中間，負相的峰不被消失。 

6 ) 13C及DEPT其中每一張圖譜它的峰的高度（intensity)須佔據它們各自框架的50 %到60 % 的高度，整張圖譜的各個部份的小圖看起來

     有一致性。 

DEPT Charting Method and Common Errors

1. Orderly Charting: In a typical NMR chart, DEPT spectra are organized sequentially: 13C at the bottom, followed by DEPT45, DEPT90, and DEPT135 at the top.

2. Peak Heights: The various peaks in each spectrum (excluding solvent peaks) should not exceed the frame limits. The heights of different 13C peaks will vary and should not be uniform, creating a varied appearance.

3. Absorption Peaks: Each peak in the DEPT spectra must be in absorption mode, not dispersion mode. This means the peaks' bottoms should be entirely positive or negative, not mixed. Peaks can be vertically stretched to check and adjust the baseline. Positive and negative peaks are relative to the baseline.

4. Consistent Heights: Ensure that the overall height of DEPT90 is consistent with the other spectra so that all spectra on the same page appear uniform and no single spectrum stands out awkwardly.

5. DEPT135 Baseline: DEPT135 displays both positive and negative phases. When charting, position the baseline in the middle of its frame so that the negative peaks are not obscured.

6. Peak Intensity: The peak height (intensity) of each spectrum (13C and DEPT) should occupy 50% to 60% of their respective frame heights. This ensures that the small spectra parts appear consistent throughout the entire chart.

By following these guidelines, you can avoid common mistakes and create clear, accurate, and consistent DEPT NMR charts.