Associate Principal Scientist Full-time

Associate Principal Scientist, Process Chemistry

The Process Chemistry organization, located at our Rahway, NJ site, is seeking a highly motivated and accomplished scientist with deep expertise in flow chemistry and continuous processing to join the Catalysis and Flow Lab. This position offers an opportunity to play a key role in advancing our pipeline of drug substances, including small molecules, macrocyclic peptides, and bioconjugates, by developing and implementing robust, sustainable, and efficient API manufacturing processes from discovery through commercialization.

The successful candidate will lead laboratory experimentation in flow chemistry, develop and implement novel continuous processing technologies, enable new chemical transformations, and influence route design across development programs. The role requires close collaboration with multidisciplinary teams, including synthetic and analytical chemists, chemical engineers, manufacturing partners, and other stakeholders, to support API campaigns at laboratory, pilot, and manufacturing scales. Responsibilities also include solving complex chemistry and processing challenges, supporting technology transfer, mentoring scientists new to the field, and contributing to the external scientific community through publications, patents, presentations, and professional engagement.

The ideal candidate will possess strong expertise in synthetic organic chemistry, process development, flow chemistry, and continuous processing, along with the passion and capability to serve as a subject matter expert within the Process Chemistry Department. A proven record of scientific innovation, technical achievement, self-initiative, and effective collaboration in a dynamic team environment is essential.

Specific Responsibilities

• Provide scientific leadership for the design, development, and optimization of scalable API processes across multiple development programs, with a strong emphasis on flow chemistry and continuous processing.
• Lead hands-on laboratory experimentation in flow chemistry to develop robust, sustainable, and efficient chemical transformations and manufacturing processes.
• Influence route design and solve complex chemistry, engineering, and manufacturing challenges through mechanistic understanding, innovative process design, and data-driven decision-making.
• Support process characterization, scale-up, technology transfer, and API campaigns at laboratory, pilot, and manufacturing scales in collaboration with cross-functional partners.
• Mentor scientists and colleagues new to flow chemistry and continuous processing while fostering a culture of scientific excellence, innovation, and collaboration.
• Contribute to the broader scientific community through publications, patents, presentations, and professional engagement.

Education

• Ph.D. in Chemistry or a related discipline.

Required Experience and Skills

• Minimum of 4 years of relevant industrial experience following completion of a Ph.D., with demonstrated success in small-molecule process chemistry using flow chemistry.
• Strong experience in organic synthesis, flow chemistry, and continuous processing, including hands-on laboratory experimentation in flow.
• Proven ability to design, develop, and optimize practical, scalable chemical processes through scientific rigor, creativity, and data-driven problem-solving.
• Ability to apply flow chemistry and continuous processing technologies to enable new chemical transformations, influence route design, and address complex process development challenges.
• Experience with automation approaches for continuous-flow process development is highly valued.
• Demonstrated success working across multidisciplinary teams and effectively communicating technical concepts to scientific and non-scientific audiences.
• Strong written communication skills, with the ability to prepare clear technical reports, presentations, publications, and documentation.
• Strong self-initiative, collaborative mindset, and enthusiasm for serving as a subject matter expert in flow chemistry while mentoring others new to the field.
• Demonstrated scientific impact through publications, patents, presentations, or participation in the broader scientific community.

Required Skills:

Automation, Chemical Reactors, Flow Chemistry, Flow Cytometry, Innovation, Laboratory Experiments, Organic Chemistry, Organic Synthesis, Production Process Development, Scientific Leadership

Preferred Skills:

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Current Contingent Workers apply HERE

US and Puerto Rico Residents Only:

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The salary range for this role is $142,400.00 – $224,100.00

This is the lowest to highest salary we in good faith believe we would pay for this role at the time of this posting. An employee's position within the salary range will be based on several factors including, but not limited to relevant education, qualifications, certifications, experience, skills, geographic location, government requirements, and business or organizational needs.

The successful candidate will be eligible for annual bonus and long-term incentive, if applicable.

We offer a comprehensive package of benefits. Available benefits include medical, dental, vision healthcare and other insurance benefits (for employee and family), retirement benefits, including 401(k), paid holidays, vacation, and compassionate and sick days. More information about benefits is available at https://jobs.merck.com/us/en/compensation-and-benefits.

You can apply for this role through https://jobs.merck.com/us/en (or via the Workday Jobs Hub if you are a current employee). The application deadline for this position is stated on this posting.

San Francisco Residents Only: We will consider qualified applicants with arrest and conviction records for employment in compliance with the San Francisco Fair Chance Ordinance

Los Angeles Residents Only: We will consider for employment all qualified applicants, including those with criminal histories, in a manner consistent with the requirements of applicable state and local laws, including the City of Los Angeles' Fair Chance Initiative for Hiring Ordinance

Search Firm Representatives Please Read Carefully Merck & Co., Inc., Rahway, NJ, USA, also known as Merck Sharp & Dohme LLC, Rahway, NJ, USA, does not accept unsolicited assistance from search firms for employment opportunities. All CVs / resumes submitted by search firms to any employee at our company without a valid written search agreement in place for this position will be deemed the sole property of our company. No fee will be paid in the event a candidate is hired by our company as a result of an agency referral where no pre-existing agreement is in place. Where agency agreements are in place, introductions are position specific. Please, no phone calls or emails.

Employee Status: Regular

Relocation: No

VISA Sponsorship: No

Travel Requirements: 10%

Flexible Work Arrangements: Not Applicable

Shift: 1st – Day

Valid Driving License: Yes

Hazardous Material(s): N/A

Job Posting End Date: 08/31/2026

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